Apparatus and techniques for electronic device encapsulation

ABSTRACT

Apparatus and techniques for use in manufacturing a light emitting device, such as an organic light emitting diode (OLED) device can include using one or more modules having a controlled environment. The controlled environment can be maintained at a pressure at about atmospheric pressure or above atmospheric pressure. The modules can be arranged to provide various processing regions and to facilitate printing or otherwise depositing one or more patterned organic layers of an OLED device, such as an organic encapsulation layer (OEL) of an OLED device. In an example, uniform support for a substrate can be provided at least in part using a gas cushion, such as during one or more of a printing, holding, or curing operation comprising an OEL fabrication process. In another example, uniform support for the substrate can be provided using a distributed vacuum region, such as provided by a porous medium.

CLAIM OF PRIORITY

This patent application is a continuation of U.S. application Ser. No.14/727,602, filed Jun. 1, 2015. U.S. application Ser. No. 14/727,602 isa continuation of PCT application no. PCT/US2015/11854, filed Jan. 16,2015. PCT application no. PCT/US2015/11854 claims benefit of priority ofeach of the following: (1) U.S. Provisional Patent Application Ser. No.61/929,668, titled “DISPLAY DEVICE FABRICATION SYSTEMS AND TECHNIQUESUSING INERT ENVIRONMENT,” filed on Jan. 21, 2014; (2) U.S. ProvisionalPatent Application Ser. No. 61/945,059, titled “DISPLAY DEVICEFABRICATION SYSTEMS AND TECHNIQUES USING INERT ENVIRONMENT,” filed onFeb. 26, 2014; (3) U.S. Provisional Patent Application Ser. No.61/947,671, titled “DISPLAY DEVICE FABRICATION SYSTEMS AND TECHNIQUESUSING INERT ENVIRONMENT,” filed on Mar. 4, 2014; (4) U.S. ProvisionalPatent Application Ser. No. 61/986,868, titled “Systems and Methods forthe Fabrication of Inkjet Printed Encapsulation Layers,” filed on Apr.30, 2014; and (5) U.S. Provisional Patent Application Ser. No.62/002,384, titled “DISPLAY DEVICE FABRICATION SYSTEMS AND TECHNIQUESUSING INERT ENVIRONMENT,” filed on May 23, 2014. All applications listedin the claim of priority herein are hereby incorporated by reference,each in its entirety.

CROSS-REFERENCE TO RELATED PATENT DOCUMENTS

This patent application is related to U.S. Patent Pub. No. US2013/0252533 A1 (Mauck, et al.), titled “GAS ENCLOSURE ASSEMBLY ANDSYSTEM,” U.S. Patent Pub. No. US 2013/0206058 A1 (Mauck, et al.), titled“GAS ENCLOSURE ASSEMBLY AND SYSTEM,” and U.S. Pat. No. 8,383,202 (Somekhet al.), titled “METHOD AND APPARATUS FOR LOAD-LOCKED PRINTING,” each ofwhich is hereby incorporated herein by reference in its entirety.

BACKGROUND

Electronic devices, such as optoelectronic devices, can be fabricatedusing organic materials, particularly using thin-film processingtechniques. Such organic optoelectronic devices can be volumetricallycompact because of their relatively thin and planar structure, alongwith providing enhanced power efficiency and enhanced visualperformance, such as compared to other display technologies. In certainexamples, such devices can be mechanically flexible (e.g., foldable orbendable), or optically transparent, unlike competing technologies.Applications for an organic optoelectronic device can include generalillumination, use as a backlight illumination source, or use as a pixellight source or other element in an electroluminescent display, forexample. One class of organic optoelectronic devices includes organiclight emitting diode (OLED) devices, which can generate light usingelectroluminescent emissive organic materials such as small molecules,polymers, fluorescent, or phosphorescent materials, for example.

In one approach, OLED devices can be fabricated in part via vacuumdeposition of a series of organic thin films onto a substrate using thetechnique of thermal evaporation. However, vacuum processing in thismanner is relatively: (1) complex, generally involving a large vacuumchamber and pumping subsystem to maintain such vacuum; (2) wasteful ofthe organic raw material, as a large fraction of the material in such asystem is generally deposited onto the walls and fixtures of theinterior, such that more material is generally wasted than depositedonto the substrate; and (3) difficult to maintain, such as involvingfrequently stopping the operation of the vacuum deposition tool to openand clean the walls and fixtures of built-up waste material.Furthermore, in OLED applications it can be desirable to deposit theorganic films in a pattern.

In another approach, a blanket coating can be deposited over thesubstrate and photolithography can be considered for achieving desiredpatterning. But, in various applications and for OLED materials inparticular, such photolithography processes can damage the depositedorganic film or the underlying organic films. A so-called shadowmask canbe used to pattern the deposited layer directly when using a vacuumdeposition technique. The shadowmask in such cases comprises a physicalstencil, often manufactured as a metal sheet with cut-outs for thedeposition regions. The shadowmask is generally placed in proximity toor in contact with, and aligned to, the substrate prior to deposition,kept in place during deposition, and then removed after deposition. Suchdirect-patterning via shadowmask adds substantial complexity tovacuum-based deposition techniques, generally involving additionalmechanisms and fixturing to handle and position the mask preciselyrelative to the substrate, further increasing the material waste (due tothe waste from material deposited onto the shadowmask), and furtherincreasing the need for maintenance to continuously clean and replacethe shadowmasks themselves. Shadowmask techniques also generally involverelatively thin masks to achieve the pixel scale patterning required fordisplay applications, and such thin masks are mechanically unstable overlarge areas, limiting the maximum size of substrate that can beprocessed. Improving scalability remains a major challenge for OLEDmanufacturing, so such limitations on scalability can be significant.

The organic materials used in OLED devices are also generally highlysensitive to exposure to various ambient materials, such as oxygen,ozone, or water. For example, organic materials used in various internallayers of an OLED device, such as including an electron injection ortransport layer, a hole injection or transport layer, a blocking layer,or an emission layer, for example, can be subject to a variety ofdegradation mechanisms. Such degradation can be driven at least in partby incorporation of chemically or electrically/optically activecontaminants into the device structure, either within the bulk materialof each film or at the interfaces between layers in the overall devicestack. Over time chemically active contaminants can trigger a chemicalreaction in the film that degrades the film material. Such chemicalreactions can occur simply as a function of time, absent any othertriggers, or can be triggered by ambient optical energy or injectedelectrical energy, for example. Electrically or optically activecontaminants can create parasitic electrical or optical pathways for theelectrical or optical energy introduced or generated in the deviceduring operation. Such pathways can result in suppression of lightoutput, or generation of incorrect light output (e.g., light output ofthe wrong spectrum.) The degradation or loss may manifest as failure ofan individual OLED display elements, “black” spotting in portions of anarray of OLED elements, visible artifacts or loss of electrical oroptical efficiency, or unwanted deviation in color rendering accuracy,contrast, or brightness in various affected regions of the array of OLEDelements.

OVERVIEW

One or more layers of an OLED device can be fabricated (e.g., depositedor patterned) using a printing technique. For example, an organicmaterial, such as for example a hole injection material, a holetransport material, an emissive material, an electron transportmaterial, a hole blocking material, or an electron injection materialcan be dissolved or otherwise suspended in a carrier fluid (e.g., asolvent), and a layer of an OLED device including the organic materialcan be formed by ink-jet printing and subsequent evaporation of thecarrier fluid to provide a patterned layer. For example, an organicmaterial, such as an organic thin film encapsulation material, can beinkjet printed in a pattern onto a substrate as a liquid mixture oforganic compounds, the patterned organic layer coating at least aportion of a light-emitting device fabricated upon the substrate andsubsequently solidified by a curing process, such by UV illumination soas to induce a cross linking reaction, thereby forming a patterned solidlayer. In another approach, a solid-phase organic material can bevaporized thermally for deposition onto a substrate through a jet. Inyet another approach, organic material can be dissolved or otherwisesuspended in a carrier liquid, and a layer of OLED device including theorganic material can be formed by dispensing a continuous stream onfluid from a nozzle onto a substrate to form a line (so-called “nozzleprinting” or “nozzle jet”) and subsequent evaporation of the carrier toprovide a line patterned layer. Such approaches can generally bereferred to as organic “printing” techniques, such as can be performedusing a printing system.

The present inventors have recognized, among other things, that printingtechniques and other processing operations can be carried out usingsystems having enclosures configured to provide a controlledenvironment, such as including an atmosphere comprising a gas that isminimally reactive or non-reactive with one or more species depositedupon or comprising a substrate being processed, such gas having aspecified purity level. Such a purity level can also include controlledmaximum impurity concentrations of other species, such as oxygen orwater, such as to prevent degradation of OLED devices during fabricationor to inhibit or suppress defects. Particulate controls can also beprovided, such as to maintain a specified particulate level within thecontrolled environment. The arrangement of enclosures can includerespective modules having individually-maintained controlledenvironments, or one or more of the modules can share a controlledenvironment with other modules. Facilities such as gas purification,temperature control, solvent abatement, or particulate control can beshared between modules or can be provided in a dedicated manner.

OLED devices being fabricated, such as substrates including many OLEDdevices, can be transferred to other fabrication equipment such as usingone or more of a loading module (e.g., a “load-lock”), a transfer moduleincluding a handler, or using techniques such as an inert or otherwisenon-reactive gas curtain and gate arrangement. In this manner, transferof a respective substrate being fabricated can occur withoutsubstantially altering an environment of the enclosed modules or withoutrequiring purging of the enclosed modules. For example, the environmentof the enclosed modules can be controlled, such as to provide anenvironment having less than 100 parts-per-million of oxygen and lessthan 100 parts-per-million of water vapor. The present inventors havealso recognized that use of a load-locked arrangement can allow forcontrolled-atmosphere-containing line elements to be integrated withother fabrication processes such as open-air or vacuum processes,without substantially altering the controlled (e.g., non-reactive andparticulate controlled) environment within a respective module, orwithout requiring time-consuming purging of the non-reactive gas volumesin each enclosed module.

The present inventors have also recognized, among other things, that aproblem can exist where active regions of a substrate are not supportedcontinuously and uniformly can exhibit non-uniformities or visibledefects during or after processing. For example, the substrate can besupported by a mechanical chuck that employs vacuum or mechanicalclamping to hold the substrate in place during processing. In oneapproach when processing substrates, lift pins can be used in centerregions of the substrate so as to raise or lower the substrate withrespect to the chuck so as to facilitate loading and unloading. In thecase of vacuum chucks, vacuum holes or grooves in the center regions ofthe substrates are generally used to hold the substrate down in place.In such an approach, holes or grooves are therefore present in thecenter region of the chuck when such generally-available supporttechniques are used and such holes or grooves can represent regions ofnon-uniform support. Without being bound by theory, such defects arebelieved to be associated with, for example, a non-uniform thermalprofile or non-uniform electrostatic field profile across the surface ofthe substrate or on a surface opposite a coating or film layer beingdeposited or treated. The present inventors have recognized that variousspecialized uniform support techniques can be used to achieve uniform,defect free coatings such as including avoiding non-uniform support inareas of the substrate upon or opposite such active regions.

For example, the present inventors have recognized, among other things,that the substrate can be uniformly supported at least in part using agas cushion, such as during one or more of a printing operation or otherprocessing such as before or during ultraviolet treatment in a curingmodule. Use of such a gas cushion can enhance uniformity of a coating orfilm layer on the substrate, such as by reducing or minimizing mura orother visible defects. In this manner, for example, an organic thin filmencapsulation layer can be printed and treated, such as using supporttechniques including a gas cushion upon or opposite active regions ofthe substrate where light emitting devices are located. In addition, orinstead, the substrate can be uniformly supported by one or more ofuniform physical contact within the active regions or by non-uniformphysical contact outside of the active region—for example, a vacuumchuck can be configured such that all of the vacuum grooves and holesand lift pin holes are confined to be outside of the active regions.Alternatively, the substrate can be uniformly supported by uniformphysical contact within those active regions for which the coatinguniformity must be maintained at a high level and supported bynon-uniform physical contact outside of the active region or withinthose active regions for which the coating uniformity need not bemaintained at a high level (e.g. for use as test devices or in lowergraded products). Alternatively (or additionally), the use of vacuumgrooves and holes can be avoided by retaining the substrate using adistributed vacuum region thereby avoiding or reducing discontinuitiesin the thermal and electrical characteristics of the structuresupporting the substrate in one or more active regions, at least withrespect to the vacuum retention mechanism.

In an example, a coating system for providing a coating on a substratecan include an enclosed printing system configured to deposit apatterned organic layer on a substrate, the patterned organic layercoating at least a portion of a light-emitting device fabricated uponthe substrate, an enclosed curing module including an ultraviolettreatment region configured to accommodate a substrate and configured toprovide an ultraviolet treatment to the patterned organic layer, and anenclosed substrate transfer module configured to receive the substratefrom an atmospheric environment different from an environment of one ormore of the enclosed printing system or the enclosed curing module. Thepatterned organic layer can occupy a deposition region of the substrateon a first side of the substrate; and the enclosed curing module can beconfigured to uniformly support the substrate in the ultraviolettreatment region using a gas cushion, the gas cushion provided to asecond side of the substrate opposite the first side, the gas cushionestablished between the substrate and a chuck.

In an example, a technique, such as a method, can include transferring asubstrate from an inorganic thin film encapsulation system to a transfermodule of an organic thin film encapsulation system, transferring thesubstrate to an enclosed printing system, the enclosed printing systemconfigured to deposit a patterned organic layer in a deposition regionon a first side of the substrate, the patterned organic layer coating atleast a portion of a light-emitting device fabricated upon thesubstrate, uniformly supporting the substrate in the enclosed printingsystem using a first gas cushion provided to a second side of thesubstrate opposite the deposition region, printing monomer over thedeposition region of the substrate using the enclosed printing system,transferring the substrate from the enclosed printing system to thetransfer module, transferring the substrate from the transfer module toan enclosed curing module, uniformly supporting the substrate in theenclosed curing module using a second gas cushion provided to the secondside of the substrate opposite the first side, and treating the monomerfilm layer in the enclosed curing module to provide a mura-freepolymerized organic layer in the deposition region.

In an example, a technique, such as a method, can include transferring asubstrate from an inorganic thin film encapsulation system to a transfermodule of an organic thin film encapsulation system, transferring thesubstrate to an enclosed printing system, the enclosed printing systemconfigured to deposit a patterned organic layer in a deposition regionon a first side of the substrate, the patterned organic layer coating atleast a portion of a light-emitting device fabricated upon thesubstrate, uniformly supporting the substrate in the enclosed printingsystem using a first uniform support provided to a second side of thesubstrate opposite the deposition region, printing monomer over thedeposition region of the substrate using the enclosed printing system,transferring the substrate from the enclosed printing system to thetransfer module, transferring the substrate from the transfer module toan enclosed curing module, uniformly supporting the substrate in theenclosed curing module using a second uniform support provided to thesecond side of the substrate opposite the first side, and treating themonomer film layer in the enclosed curing module to provide a mura-freepolymerized organic layer in the deposition region. One or more of thefirst or second uniform support regions can include a distributed vacuumregion in physical contact with the substrate or a gas cushion.

In an example, a coating system for providing a coating on a substratecan include an enclosed printing system configured to deposit apatterned organic layer on a substrate, the patterned organic layercoating at least a portion of a light-emitting device being fabricatedupon the substrate, the enclosed first printing system configured toprovide a first processing environment, an enclosed curing moduleincluding a stacked configuration of ultraviolet treatment regions, theultraviolet treatment regions offset from each other and each configuredto accommodate a substrate, the enclosed curing module configured toprovide a second processing environment, an enclosed substrate transfermodule comprising a chamber configured to receive the substrate from anatmospheric environment different from the environment of one or more ofthe enclosed printing system or the enclosed curing module. The firstand second processing environments can include controlled environmentsat or near atmospheric pressure and established to remain belowspecified limits of limits of particulate contamination level, watervapor content, and oxygen content.

The systems and techniques described herein can be used in support ofmanufacturing a range of different electronic device configurations,such as including one or more optoelectronic devices. For example, aflat panel display device can be fabricated at least in part usingsystems or techniques described herein. Such a flat panel display devicecan include an organic light emitting diode (OLED) flat panel display.Several OLED flat panel displays can be processed on a substrate (or“mother” glass). Use of the word “substrate” or the phrase “substratebeing fabricated” refers generally to an assembly in-process that caninclude an OLED device. The examples herein need not be restricted to aparticular panel geometry or size. For example, such systems andtechniques can be used in support of fabrication of display devices onsubstrates having a generation 2 (“Gen 2”) size, such as having arectangular geometry including dimensions of about 37 centimeters (cm)by about 47 cm. The systems described herein can also be used forsomewhat larger substrate geometries, such as in support of fabricationof display devices on substrates having a generation 3.5 (“Gen 3.5”)substrate size, such as having a rectangular geometry includingdimensions of about 61 centimeters (cm) by about 72 cm. The systemsdescribed herein can also be used for even larger substrate geometries,such as in support of fabrication of display devices on substrateshaving a substrate size corresponding to “Gen 5.5,” having dimensions ofabout 130 cm×150 cm, or a “Gen 7” or “Gen 7.5” substrate, havingdimensions of about 195 cm×225 cm. For example, a Gen 7 or Gen 7.5substrate can be singulated (e.g., cut or otherwise separated) intoeight 42 inch (diagonal dimension) or six 47 inch (diagonal dimension)flat panel displays. A “Gen 8” substrate can include dimensions of about216×246 cm. A “Gen 8.5” substrate can include dimensions of about 220cm×250 cm, and can be singulated to provide six 55 inch or eight 46 inchflat panels per substrate.

Dimensions beyond Gen 8.5 can be supported using systems and techniquesdescribed herein. For example, a “Gen 10” substrate having dimensions ofabout 285 cm×305 cm, or beyond, can be fabricated at least in part usingsystems and techniques described herein. The panel sizes describedherein, while generally applicable to glass substrates, can applied tosubstrates of any material suitable for use in display devicefabrication, and in particular OLED display fabrication that can includeforming one or more layers using printing techniques. For example, avariety of glass substrate materials can be used, as well as a varietyof polymeric substrate materials, for example, polyimide.

This overview is intended to provide an overview of subject matter ofthe present patent application. It is not intended to provide anexclusive or exhaustive explanation of the invention. The detaileddescription is included to provide further information about the presentpatent application.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A illustrates generally an example of a plan view of at least aportion of a system, such as including a printing system and a curingmodule, that can be used in manufacturing an electronic device (e.g., anorganic light emitting diode (OLED) device).

FIG. 1B and FIG. 1C illustrate generally illustrative examples ofisometric views of at least a portion of a system, such as including aprinting system and a curing module, that can be used in manufacturingan electronic device (e.g., an organic light emitting diode (OLED)device).

FIG. 2A illustrates generally an example of a plan view of at least aportion of a system that can be used in manufacturing a light emittingdevice (e.g., an OLED device).

FIG. 2B illustrates generally an isometric view of at least a portion ofa system that can be used in manufacturing a light emitting device(e.g., an OLED device).

FIG. 3A illustrates generally an isometric view of at least a portion ofa system, such as including a printing system and other modules.

FIG. 3B illustrates generally a plan view of at least a portion of asystem, such as can include a printing system and other modules.

FIG. 3C illustrates generally a further example of a plan view of atleast a portion of a system, such as can include a printing system andother modules.

FIG. 4A and FIG. 4B illustrate techniques, such as methods, that caninclude forming an organic thin-film encapsulation layer (OTFEL) of alight emitting device (e.g., an OEL of an OLED device).

FIG. 5 illustrates generally an example of a diagram illustrating aportion of an ultraviolet treatment system that can be used inmanufacturing a light emitting device.

FIG. 6 illustrates generally an example of a diagram illustrating anultraviolet treatment system that can be used in manufacturing a lightemitting device.

FIG. 7A and FIG. 7B illustrate generally examples of at least a portionof an ultraviolet treatment system that can include a linearconfiguration of ultraviolet sources, such as can be used inmanufacturing a light emitting device.

FIG. 8A and FIG. 8B illustrate generally examples of at least a portionof an ultraviolet treatment system that can include a linearconfiguration of ultraviolet sources and a photodetector.

FIG. 9 illustrates generally an example of a diagram illustrating aportion of an ultraviolet treatment system that can include atwo-dimensional array configuration of ultraviolet sources, such as canbe used in manufacturing a light emitting device.

FIG. 10 illustrates generally an example of a two-dimensional arrayconfiguration of ultraviolet sources, such as can be used as a portionof an ultraviolet treatment system.

FIG. 11 illustrates generally an example of a housing configuration foran array of ultraviolet sources, such as can be included as a portion ofan ultraviolet treatment system.

FIG. 12 illustrates generally an illustrative example of an intensityplot showing a non-uniformity of delivered ultraviolet energy, such ascan be used to establish an inverse or normalization filterconfiguration.

FIG. 13A and FIG. 13B illustrate generally illustrative examples of achuck configuration that includes ports or grooves in contact with asubstrate in FIG. 13A, such as during one or more of a deposition,holding, material flow or dispersal, or cure process, and correspondingvisible non-uniformities (e.g., “mura”) in a layer of the substrate inFIG. 13B.

FIG. 14A, FIG. 14B, FIG. 14C, and FIG. 14D include illustrative examplesdepicting various regions of a substrate, and corresponding fixturessuch as a chuck or end effector that can include one or more pressurizedgas ports, vacuum ports, or vacuum regions.

FIG. 15A and FIG. 15B illustrate generally illustrative examples of achuck configuration that can include a combination of one or moremechanical support pins and one or more vacuum regions

FIG. 16A and FIG. 16B, by contrast with FIGS. 13A and 13B, includeillustrative examples of a chuck configuration that can include portsconfigured to establish a pressurized gas cushion to support a substratein FIG. 16A, such as during one or more of a deposition (e.g.,printing), holding, or cure process, and a corresponding uniformity inthe resulting substrate in FIG. 16B.

FIGS. 16C and 16D, by contrast with FIGS. 13A and 13B, illustrategenerally illustrative examples of a chuck configurations that include aporous medium, such as to establish a distributed vacuum or pressurizedgas cushion during one or more of a deposition (e.g., printing),holding, material flow or dispersal, or cure process, such as providinguniformity in the resulting substrate as shown in FIG. 16E.

FIG. 16E illustrates generally and illustrative example of a resultingsubstrate, such as can be provided using a chuck configuration shown inFIG. 16C or FIG. 16D.

FIG. 17 illustrates generally a schematic representation of a gaspurification scheme that can be used in relation to portions orentireties of one or more other examples described herein, such as toestablish or maintain an controlled environment in an enclosure housingfabrication equipment used in manufacturing a light emitting device(e.g., an OLED device).

FIGS. 18A and 18B illustrate generally examples of a gas enclosuresystem for integrating and controlling non-reactive gas and clean dryair (CDA) sources such as can be used to establish the controlledenvironment referred to in other examples described elsewhere herein,and such as can include a supply of pressurized gas for use with afloatation table.

FIGS. 19A and 19B illustrate generally examples of a gas enclosuresystem for integrating and controlling non-reactive gas and clean dryair (CDA) sources such as can be used to establish the controlledenvironment referred to in other examples described elsewhere herein,and such as can include a blower loop to provide, for example,pressurized gas and at least partial vacuum for use with a floatationtable.

FIG. 19C illustrates generally a further example of a system forintegrating and controlling one or more gas or air sources, such as toestablish floatation control zones included as a portion of a floatationconveyance system.

FIG. 20A, FIG. 20B, and FIG. 20C illustrate generally views of at leasta portion of a system, such as including a transfer module, that can beused in manufacturing an electronic device (e.g., an organic lightemitting diode (OLED) device).

FIG. 21A and FIG. 21B illustrate generally views of a portion of asystem, such as can include a stacked configuration of substrateprocessing areas that can be used in manufacturing an electronic device(e.g., an organic light emitting diode (OLED) device).

FIG. 22A illustrates generally a portion of a system, such as includinga transfer module coupled to other chambers or modules, that can be usedin manufacturing an electronic device (e.g., an organic light emittingdiode (OLED) device).

FIG. 22B illustrates generally a handler configuration that can be used,such as for manipulating a substrate within the module shown in FIG.22A.

In the drawings, which are not necessarily drawn to scale, like numeralsmay describe similar components in different views. Like numerals havingdifferent letter suffixes may represent different instances of similarcomponents. The drawings illustrate generally, by way of example, butnot by way of limitation, various embodiments discussed in the presentdocument.

DETAILED DESCRIPTION

FIG. 1A illustrates generally an example of a plan view of at least aportion of a system 1000A, such as including a printing system 2000 anda processing module 1300, that can be used in manufacturing anelectronic device (e.g., an organic light emitting diode (OLED) device).For example, the system 1000A can be used to form an organic thin filmencapsulation layer (OTFEL) upon a substrate containing one or moreelectronic devices.

Similar to other examples described herein, the system 1000A can includea printing system 2000 (e.g., to “print” or otherwise deposit a filmencapsulation layer onto a substrate). The system 1000A can include atransfer module 1400. One or more processing modules such as aprocessing module 1300 can be coupled to the transfer module 1400. As inother examples described herein, each of the printing system 2000, thetransfer module 1400, and processing module 1300 can be enclosed, suchas to provide a controlled environment at about atmospheric pressure orabove atmospheric pressure (e.g., a nitrogen environment having aspecified maximum level of one or more impurity species). Substrates canbe transferred to or from the system 1000A such as using a loadingmodule 1100. In this manner, respective controlled environments in oneor more other portions of the system 1000A can be maintained withoutcontamination or without requiring purging of an entirety of suchcontrolled environments during transfer of a substrate into or out ofthe system 1000A. The processing module 1300 can be configured toperform one or a variety of processing operations, such as one or moreof a holding operation, a curing operation (e.g., using heat or exposureto ultraviolet radiation to treat a substrate, for example), a bufferingoperation, or one or more other operations.

The system 1000A of FIG. 1A can be stand-alone, or can be integratedwith other elements, such as shown in other examples herein. The system1000A of FIG. 1A can operate in aggregate in a cluster or in-line mode.For example, in a cluster mode, substrates can be loaded and unloadedfrom loading module 1100. For example, in an in-line mode, substratescan be loaded into the left side of printing system 2000 and unloadedfrom loading module 1100.

FIG. 1B and FIG. 1C illustrate generally illustrative example offront-facing and rear-facing isometric views of at least a portion ofthe system 1000A that can be used in manufacturing a light emittingdevice (e.g., an OLED device), such as for fabricating an OTFEL of anOLED device according to the techniques illustrated in FIG. 4A or 4B.The system 1000A can include a loading module 1100 for transfer of oneor more substrates into or out of a controlled environment within one ormore portions of the system 1000A, such as using a handler located in atransfer module 1400.

The system 1000A can include a printing system 2000, such as having aconveyor extending through a first region 2100, a printing region 2200,and second region 2300, similar to other printing system examplesdescribed herein. Substrates to be processed can be queued or can beheld to provide a specified holding duration to allow flowing ordispersal of an organic material deposited upon the substrate by theprinting system 2000. For example, one or more of a first module 1200, asecond module 1300, or a third module 8500 can be used for holding oneor more substrates before printing or after printing. The configurationof the one or more modules 1200, 1300, or 8500 can be specified at leastin part using information about the substrate panel size.

As an illustrative example, for a configuration for organicencapsulation layer (OEL) fabrication for a Gen 3.5 substrate geometryor a ¼ Gen 5 substrate geometry, the first module 1200 can be used as anencapsulation layer holding module and a curing module, such asproviding uniform support for the substrate using one or more of thetechniques described elsewhere herein (e.g., using a gas cushion orotherwise uniformly supporting the substrate using uniform physicalcontact inside the “active” regions where light emitting devices areformed on the substrate). The inventors have recognized, among otherthings, that uniform support techniques described below including gasfloatation (or alternatively uniform physical contact inside the“active” regions) during one or more of printing, holding, or curingoperations can suppress or inhibit formation of visible non-uniformities(e.g., mura) in an OEL fabrication process.

The second module 1300 can be used as a reorientation module. Thereorientation module can provide a volume in which a handler can flip orrotate a substrate being fabricated. The third module 8500 can include aholding module such as to store substrates in environmentally-controlledregions in a stacked configuration such as shown illustratively inexamples elsewhere herein (e.g., as shown in FIG. 21A or FIG. 21B). Inanother example, such as for a larger substrate geometry, the thirdprocessing module 8500 can be configured to provide a reorientationmodule, the first processing module 1200 can be configured to provide anencapsulation curing module, and the second processing module 1300 canbe configured as a holding or buffering module having one or moreenvironmentally-controlled regions. Other configurations can be used,such as shown illustratively in the examples of FIG. 2A or 2B, such ascan be used with large panel geometries or to enhance throughput.

A controlled environment within one or more enclosed portions of thesystem can include specifications such as including one or more of (1)better than Class 10 particle control for particles greater than orequal to two micrometers in diameter, (2) less than 10 parts-per-millionof each of water and oxygen or less than 1 part-per-million of each ofwater and oxygen, or (3) temperature control of the ambient gasenvironment to within plus or minus 2 degrees Celsius.

While the illustrations of FIGS. 1A and 1B show a single processingmodule 1200 coupled to the transfer module 1400A, other configurationsare possible. FIG. 2A illustrates generally an example of a plan view ofat least a portion of a system 1000B, such as including a printingsystem 2000, first and second processing modules 1200A and 1200B, and athird processing module 1300, that can be used in manufacturing anelectronic device (e.g., an organic light emitting diode (OLED) device)and FIG. 2B illustrates generally an illustrative example of anisometric view of at least a portion of the system 1000B.

The system 1000B can include first and second transfer modules 1400A and1400B coupled to the printing system 2000. One or more other modules canbe coupled to the printing system 2000, such as through the transfermodule 1400A or the second transfer module 1400B. For example, the firstprocessing module 1200A can be coupled to the first transfer module1400A, and the second and third processing modules 1200B and 1300 can becoupled to the second transfer module 1400B.

The first, second, or third processing modules 1200A, 1200B, or 1300 caninclude a holding or buffer module, a curing module, or one or moreother modules. One or more of the first, second, or third processingmodules can include a stacked configuration, such as shownillustratively in the examples of FIG. 5, FIG. 21A, or FIG. 21B. Inaddition to simply holding substrates for the purpose of substrate flowmanagement, such as holding a substrate for a period of time untilanother module is ready to receive it or providing a place to holddefective or damaged substrates until they can be removed, a holding orbuffer module can also be used to hold substrates for a period of timeas a part of a functional process flow.

For example, after a printing operation, the substrate can be held forin a holding module, such as to provide a specified duration fordispersal or flowing of an organic material printed upon the substrate,such as during a process for forming an organic encapsulation layer.Such a holding operation can have a specified duration. In anotherexample, the substrate can be held (e.g., for a specified duration), ina curing module, such as before enabling ultraviolet or heat treatmentof the substrate. Such timed holding operation can be performed to allowthe substrate to evolve from one state to another. For example, after aprinting operation in which a liquid material is deposited onto thesubstrate and prior to a curing operation to form a solid film, a timedholding operation having a specified duration may be used to allow theliquid to flow, settle, dry, or any combination of the three prior tofixing the film via a curing operation, such as a curing operationincluding thermal treatment or optical treatment.

The first, second, or third processing modules 1200A, 1200B, or 1300 caninclude a vacuum drying module, such as can accommodate a singlesubstrate or multiple substrates, such as in a stacked configuration, asshown illustratively in FIG. 21A or FIG. 21B. Such a vacuum dryingmodule can provide for the drying (at pressures below ambient pressures)of a liquid material, such as can be deposited onto the substrate viaprinting. In an example, the system 1000B can include both a holdingmodule providing various functions as described above and a separatevacuum drying module. Alternatively (or in addition), the system 1000Bcan include a holding module configured to provide holding or bufferingat ambient pressure, or at about ambient pressure during certaindurations, and to provide vacuum drying during other durations.

The system 1000B can be enclosed, such as having an controlledprocessing environment. Such a controlled processing environment can beestablished to remain below specified limits of one or more ofparticulate contamination level, water vapor content, oxygen content,and organic vapor content. For example, the controlled processingenvironment can include nitrogen or another gas or mixture of gasesspecified for minimal or no reactivity with a species deposited on asubstrate being processed using the system 1000B. As described in otherexamples below, such a controlled processing environment can beestablished at least in part using a gas purification system includewithin or coupled to various portions of the system 1000B (e.g., asshown in FIG. 17, FIG. 18A, FIG. 18B, FIG. 19A, FIG. 19B, or FIG. 19C).A particulate level of the controlled environment can also becontrolled, such as using apparatus coupled to the system 1000B orlocated within one or more modules of the system 1000B, as shown anddescribed in other examples herein.

As an illustrative example, one or more of the first, second, or thirdprocessing modules 1200A, 1200B, or 1200C, the printing system 2000, orthe transfer module 1400A, can include an controlled environmentestablished by a shared gas purification facility, a single dedicatedgas purification facility, or multiple dedicated gas purificationfacilities individually associated with different portions of the system1000B. For example, various modules can include gates or valving such asto be controllably isolated from other portions of the system 1000B toallow various operations as might be performed during nominal systemoperation or during maintenance, without requiring an entirety of thecontrolled environment of the system 1000B to be purged or otherwisecontaminated.

The system 1000B can include one or more loading modules, such as one ormore of a first loading module 1100A or a second loading module 1100B,such as to provide a point-of-entry or point-of-exit for one or moresubstrates being fabricated. The first or second loading modules 1100Aor 1100B can be fixed or removable, such as directly coupling the system1000B to other apparatus in a manufacturing line, or even providing aremovable assembly that can be transported to or from other apparatus.For example, one or more of the first or second loading modules 1100A or1100B can be configured to transfer the substrate to or from anenvironment different from the environment within the system 1000B.

For example, the first loading module 1100A or second loading module1100B can be coupled to a vacuum source, or a purge source, or both, andcan be configured for independently sealing the interface port to system1000B and the interface port to the prior or next environment (whichcould be the ambient environment or a controlled environment associatedwith another enclosed processing module). In this manner, the first orsecond loading modules 1100A or 1100B can internally seal itself andtransition the internal environment of the loading modules 1100A or1100B between one that is not compatible with system 1000B to one thatis compatible with system 1000B (e.g., a controlled environment at aboutatmospheric pressure or above atmospheric pressure that when exposed tosystem 1000B via the interface port would substantially maintain thequality of the controlled environment in system 1000B). Similarly, thefirst loading module 1100A or second loading module 1100B can be used totransfer the substrate to an environment suitable for other processing(e.g., a second environment at or near atmospheric pressure but having adifferent composition than the controlled environment, or a vacuumenvironment). In this manner, the first or second loading modules 1100Aor 1100B can provide a transfer conduit between the controlledenvironment of the system 1000B and other apparatus.

As mentioned above, the first loading module 1100A or the second loadingmodule 1100B can include a permanently-attached configuration, or a cartor other transportable configuration. A substrate being fabricated canbe placed within one of the loading modules 1100A or 1100B through aport, such as using a handler located within the system 1000B, or usingone or more handlers located elsewhere, such as a first handler (e.g., arobot) located within the first transfer module 1400A or elsewhere, or asecond handler located within the second transfer module 1400B orelsewhere.

In an example, a loading module (e.g., the first loading module 1100A orthe second loading module 1100B) can then be provided with anon-reactive atmosphere or otherwise “charged” using a purified gasstream, such as including one or more purge operations, to prepare aninterior region of the loading module (e.g., the first loading module1100A or the second loading module 1100B) for exposure to interiorportions of the enclosed system 1000B. For example, an internal regionof one or more of the first or second loading modules can be at leastpartially evacuated or purged in order to avoid contamination in amanner exceeding the specified limits of particulate contaminationlevel, water vapor content, oxygen content, ozone content, and organicvapor content of the controlled processing environment within anenclosed region defined by other portions of the system 1000B.

Similarly, after processing by the system 1000B, a substrate beingprocessed can be placed in the first or second loading modules 1100A or1100B. As an illustration, the loading module (e.g., the first loadingmodule 1100A or the second loading module 1100B) can be isolated from anon-reactive gas environment elsewhere in the system 1000B, such ascoupled to a vacuum source to be evacuated for subsequent processingunder vacuum conditions, or otherwise for transport of the substratebeing fabricated to other apparatus or processing under vacuumconditions, ambient conditions or some other static controlledenvironment. As a further illustration, one of the first or secondloading modules 1100A or 1100B can be configured to provide thesubstrate to the controlled processing environment within the system1000B without raising a concentration of a reactive species by morethan, for example, 1000 parts per million within the enclosed region orsimilarly, without raising the ambient particle levels by more than aspecified amount, or without depositing more than a specified number ofparticles of specified size per square meter of substrate area onto thesubstrate.

In an example, the first loading module 1100A can be coupled to thetransfer module 1400A by a port (e.g., including a physical gate havinga substantially gas impermeable seal) or gas curtain. When the port isopened, an interior of the first loading module 1100A can be accessed bya handler located in the first transfer module 1400A. The handler caninclude a robotic assembly having various degrees of freedom, such as tomanipulate a substrate using an end effector. Such an end effector caninclude a tray or frame configured to support the substrate by gravity,or the end effector can securely grasp, clamp, or otherwise retain thesubstrate, such as to allow reorientation of the substrate from aface-up or face-down configuration to one or more other configurations.Other end effector configurations can be used, such as includingpneumatic or vacuum-operated features to either actuate portions of theend effector or otherwise retain the substrate. Further illustrativeexamples of transfer modules including handlers, and various endeffector configurations are described below.

In aggregate, the system 1000B can be operated in so-called “cluster”and “linear” (or “in-line”) modes, these two operating modes beingmainly differentiated by the flow of a substrate in from and then backto the same chamber in the “cluster” mode and the flow of a substrate infrom one chamber and out to a different chamber in the “linear” or“in-line” mode. The subject matter described herein can be included orused in both “cluster” and “linear” or “in-line” configurations.

In an example, the first transfer module 1400A can position a substrateto be located in an input enclosure region 2100 of a printing system,such as located on a conveyer. The conveyer can position the substrateat a specified location within the printing module such as using one ormore of physical mechanical contact or using gas cushion to controllablyfloat the substrate (e.g., an “air bearing” table configuration). Anillustrative example of floatation control zones, such as can beincluded for floatation-type conveyance is illustrated in FIG. 19C.

A printer region 2200 of the system 1000B can be used to controllablydeposit one or more film layers on the substrate during fabrication. Theprinter region 2200 can also be coupled to an output enclosure region2300 of the printing module. The conveyer can extend along the inputenclosure region 2100, the printer region 2200, and the output enclosureregion 2300 of the printing module, and the substrate 4000 can berepositioned as desired for various deposition tasks, or during a singledeposition operation. The controlled environments within the inputenclosure region 2100, the printer region 2200, and the output enclosureregion 2300 can be commonly-shared.

The printer region 2200 can include one or more print heads, e.g. nozzleprinting, thermal jet or ink-jet type, coupled to or otherwisetraversing an overhead carriage, such as configured to deposit one ormore film layers on the substrate in a “face up” configuration of thesubstrate. Such layers can include one or more of an electron injectionor transport layer, a hole injection or transport layer, a blockinglayer, or an emission layer, for example. Such materials can provide oneor more electrically functional layers. Other materials can be depositedusing printing techniques, such as a monomer or polymer material, asdescribed in other examples described herein, such as for providing oneor more encapsulation layers for a substrate being fabricated.

After deposition of one or more layers onto the substrate 4000, thesystem 1000 can include a second transfer module 1400B, such asincluding a second handler 1410B that can be similar to the firsthandler 1410A. The substrate 4000 can be manipulated by the secondhandler 1410B, such as accessed using the output enclosure region 2300of the printing module. The second handler 1410B can be isolated fromthe printing module, such as using a gate or other arrangement. A secondprocessing module 1300, such as having an controlled environment, can becoupled to the second transfer module 1400B, such as to provide a bufferhaving one or more environmentally-controlled regions, or to provide oneor more other capabilities supporting fabrication. The system caninclude a second loading module 1100B, such as similar to the firstloading module 1100A. The second loading module can be used to transfersubstrates out of the system 1000, such as after one or more depositionoperations involving the printing module, or after other processing.

According to various examples, the first or second processing modules1200 or 1300 can provide other processing, such as for drying or solventevaporation. Other examples can include ultraviolet exposure, substrateholding (e.g., to facilitate material flow or dispersal after printingand before curing, so as to achieve a more planar or uniform coating),reorientation (e.g., to rotate the substrate 4000), holding, orbuffering (e.g., storage of substrates in-process in a controlledenvironment such as in a queued fashion).

Use of a gas cushion arrangement to uniformly support the substrateduring one or more of printing or other processing operations such assubstrate holding (e.g., to facilitate material flow or dispersal) orfilm curing can reduce or suppress formation of visible defects (e.g.,“mura”) in active regions of the substrate. For example, such activeregions can be defined as portions of the area of the substrate wherelight emitting electronic devices are being fabricated or encapsulated.

FIG. 3A illustrates generally an isometric view and FIG. 3B illustratesgenerally a plan view of at least a portion of a system 3000A, such asincluding a first printing system 2000A, a second printing system 2000B,and other modules, that can be used in manufacturing an electronicdevice (e.g., an organic light emitting diode (OLED) device).

The system 3000A can include a first printing system 2000A, such as aprinting system as described in relation to other examples herein. Inorder to provide one or more of increased throughput, redundancy, ormultiple processing operations, other printing systems can be included,such as a second printing system 2000B. The system 3000A can alsoinclude one or more other modules, such as first processing module 1200or a second processing module 1300.

As mentioned above, the first or second processing modules 1200 or 1300can be used for one or more of holding a substrate (e.g., to facilitateflowing or dispersing the deposited material layer, such as to achieve amore planar or uniform film) or curing (e.g. via UV light illumination)a layer of material, such as deposited by one or more of the first orsecond printing modules 2000A or 2000B. For example, as describedelsewhere herein, a material layer that flows or disperses, or is cured,using the first or second processing modules 1200 or 1300 can include aportion of an encapsulation layer (such as a thin film layer comprisingan organic encapsulant cured or treated via exposure to ultravioletlight). The first or second processing modules 1200 or 1300 can beconfigured for holding substrates as described above, such as in astacked configuration. Processing module 1300 could alternatively (oradditionally) be configured for vacuum drying one or more substrates,such as in a stacked configuration. In the case that one or more of thefirst or second processing modules 1200 or 1300 function as a vacuumdrying module for more than one substrate at a time, the stackedconfiguration can include multiple drying slots in a single chamber or astack of isolated chambers, each having a single drying slot. In yetanother configuration, one or more of the first or second processingmodules 1200 or 1300 can be configured for holding substrates andanother processing module can be provided attached to transfer module1400A for vacuum drying one or more substrates. The first and secondprinters 2000A and 2000B can be used, for example, to deposit the samelayers on the substrate or printers 2000A and 2000B can be used todeposit different layers on the substrate.

The system 3000A can include a input or output module 1101 (e.g., a“loading module”), such as can be used as a load-lock or otherwise in amanner that allows transfer of a substrate 4000 into or out of aninterior of one or more chambers of the system 3000A in a manner thatsubstantially avoids disruption of a controlled environment maintainedwithin one or more enclosures of the system 3000A. For example, inrelation to FIG. 3A and other examples described herein, “substantiallyavoids disruption” can refer to avoiding raising a concentration of areactive species by a specified amount, such as avoiding raising such aspecies by more than 10 parts per million, 100 parts per million, or1000 parts per million within the one or more enclosures during or aftera transfer operation of a substrate 4000 into or out the one or moreenclosures. A transfer module 1400B, such as can include a handler1410B, can be used to manipulate the substrate 4000 before, during, orafter various operations. An example of a configuration that can be usedfor the transfer module 1400B is shown illustratively in FIGS. 22A and22B. One or more additional handlers can be included, such as to providea substrate to the input or output module 1101 or receive a substratefrom the input or output module 1101.

FIG. 3C illustrates generally a further example of a plan view of atleast a portion of a system 3000B, such as can be used in manufacturingan electronic device (e.g., an organic light emitting diode (OLED)device). In FIG. 7C, first and second printing systems 2000A and 2000Bcan be arranged similarly to the example of FIGS. 7A, 7B (e.g., fordepositing different or similar layers on a substrate). The system 3000Bcan be extended as compared with the example of system 3000A, such asincluding first and second processing modules 1200A and 1200B, and thirdand fourth processing modules 1300A and 1300B. As an illustrativeexample, the processing modules 1200A, 1200B, 1300A, or 1300B caninclude curing modules configured to provide ultraviolet treatment orcan be configured to hold one or more substrates for any of the holdingfunctions described elsewhere. Other arrangements are possible. Forexample, the examples of FIGS. 3A, 3B, and 3C illustrate generally aconfiguration that can include two printing systems 2000A and 2000B, butmore than two printing systems can be included. Similarly, additional(or fewer) processing modules can be included.

FIG. 4A and FIG. 4B illustrate techniques, such as methods, that caninclude forming an organic thin-film encapsulation layer (OTFEL) of alight emitting device (e.g., an OEL of an OLED device). In the example4100 of FIG. 4A, at 4200, as substrate can be transferred from aninorganic thin film encapsulation system to a transfer chamber of anorganic thin film encapsulation (OTFE) system, such as a system as shownand described in relation to other examples herein. The substrate can betransferred from an environment different from a controlled environmentof the transfer module, such as using loading module (e.g., “loadlock”). At 4300, the substrate can be transferred to an enclosedprinting system, such as at least in part using a handler robot locatedwithin the transfer module or within the enclosed printing system. At4400, the substrate can be uniformly supported in the printing system,such as using techniques and apparatus to reduce or inhibit formation ofvisible defects or “mura” during printing operations or otheroperations.

For example, such support can include a chuck configuration (e.g., aplanar chuck or tray) such as configured to provide uniform physicalcontact in areas of the substrate upon or opposite regions of thesubstrate where active devices such as light emitting electronic deviceshave been formed. This, however, can present a variety of challengesbecause generally-available chucks generally provide holes in centralregions of the substrate through which lift pins can raise and lower thesubstrate, so as to facilitate loading and unloading operations. Theseholes can represent regions of non-uniform physical contact with thesubstrate. In the example of a vacuum chuck, there can also be groovesor holes through which the vacuum suction is provided that holds thesubstrate in place, and generally some of such groove or hole featuresare located in the central region of the substrate to achieve desiredhold-down performance.

The present inventors have recognized, among other things, that asupport chuck (or other portion of the system supporting the substrate),can be configured so as to position chuck features to minimize oreliminate their impact on the target coating pattern. In an example, thechuck can further provide non-uniform physical contact to certain areasof the substrate upon or opposite regions of the substrate outside whereactive devices such as light emitting electronic devices have beenformed, or where active devices such as light emitting devices have beenformed but which do not have a strict uniformity requirement—forexample, devices that will only be used for testing or which aremanufactured and sold as second grade product. In this example, lightemitting electronic devices are used as just one illustrative example,but the same support structure configurations can be applied to anyactive electronic, optical, or optoelectronic devices, wherein theactive region can represent a region within which the devices beingencapsulated are located.

The approach mentioned above to physically supporting the substrate innon-active areas has the benefit of being simple and relatively lowcost, it does suffer from a drawback that in most instances such anapproach includes portions of the center region of the substrate thatare restricted from use for top quality uniform coatings, therebyreducing an effective productivity of the system. The present inventorshave also recognized that such a drawback can be addressed by using adistributed vacuum region instead of individual vacuum grooves or holes,such as a continuous porous medium through which vacuum suction isprovided. Remaining holes in the chuck associated with the lift pins canbe restricted to one or more of a periphery of the substrate or aperiphery of active regions (including regions opposite a surfacedefining a periphery of the substrate or a periphery of active regionsof the substrate).

Alternatively, for example, the present inventors have also recognized,among other things, that the substrate can be uniformly supported atleast in part using a gas cushion, such as during one or more of aprinting operation or other processing such as before or duringultraviolet treatment in a curing module. Use of such a gas cushion canenhance uniformity of a coating or film layer on the substrate. Forexample, by floating the substrate above a physical substrate supportsurface, the substrate sees a uniform gas in all of the supportedregions and is relatively less sensitive to the presence of holes forlift pins or other localized features that may be present on physicalsubstrate support surface. In such a floating support example, lift pinsin the center region of the substrate can be incorporated into thesupport mechanism without affecting film uniformity in those areasbecause the substrate is not in physical contact with extended orretracted lift pins and is supported by a gas cushion in the centerregion during processing such as printing, holding, or curing. Inaddition, or instead, the substrate can be further uniformly supportedor retained by physical contact restricted to regions outside suchactive regions, such as in one or more of the substrate periphery or aperiphery between active regions. In this way, all of the substrate areacan offer a highly uniform coating and can be used productively, except,potentially, for an exclusion zone at the substrate edge where thesubstrate is physically contacted so as to constraint or hold it inplace in the floatation plane.

At 4500, an organic material such as a monomer can be printed in atarget deposition region of the substrate, such as including a monomerto form an organic encapsulation layer. The phrase “deposition region”generally refers to the region where the organic encapsulation layer isbeing formed. At 4600, the substrate can be transferred from theprinting system to the transfer module. In an example, the substrate isretained in the enclosed printing system for a specified holdingduration after printing to allow flowing or dispersal of an organicmaterial deposited upon the substrate by the printing system. At 4700,the substrate can be transferred from the transfer module to a curingmodule.

At 4800, the substrate can be supported in the curing system, such asuniformly supported in one or more specified regions. The manner ofsupporting the substrate can be similar to or different from thesubstrate support technique used during the printing operation at 4500.However, generally, the substrate support can again provide uniformsupport, such as via uniform physical contact (e.g., a vacuum chuck suchas providing a distributed vacuum region) or gas floatation, withinthose active areas to be uniformly coated, during printing, curing, orholding operations (e.g., during which a material flows or dispersesprior to curing). For example, a chuck configured to support thesubstrate at least in part using a gas cushion. The curing module can beconfigured to treat the printed organic material at 4900, such as toprovide a mura-free OTFE layer. For example, the curing module can beconfigured to provide optical treatment, such as an ultraviolet lighttreatment, to a printed monomer layer to polymerize or otherwise curethe monomer layer.

FIG. 4B illustrates another example 4150, such as for providing amura-free OTFE layer. At 4200, as in the example of FIG. 4A, a substratecan be transferred from an ITFE system to a transfer chamber of an OTFEsystem. At 4350, the substrate can be transferred to a substrate supportsystem of a printing system, such as to provide uniform support of thesubstrate at least in one or more active regions of the substrate. Sucha substrate support system can include apparatus or techniques asmentioned above to help suppress or inhibit mura formation during one ormore operations such as printing or holding (e.g., prior to curing so asto facilitate the dispersal or flow of the deposited material). Forexample, the substrate support system can include a floatation tableconfiguration, such as having various floatation control zones includingone or more of a pneumatically-supplied gas cushion, or a combination ofpneumatic and at least partial vacuum supplied regions to provide a gascushion supporting the substrate. In another example, a distributedvacuum region can be used such as to provide uniform support of thesubstrate at least in one or more active regions of the substrate. At4550, a monomer can be printed over a target deposition region.

At 4600, the substrate can be transferred from the printing system tothe transfer chamber, such as using a handler located in the transferchamber, as mentioned above in relation to FIG. 4A. At 4750, thesubstrate can be transferred from the transfer chamber to a substratesupport system of an OTFE curing module. The substrate support systemcan include a chuck configured to support the substrate in a manner thatcan suppress or inhibit mura formation during one or more of a holdingoperation or curing operation. For example, as described in otherexamples, the substrate can be held for a specified duration afterprinting and before treatment by the curing module, such as beforeultraviolet treatment. At 4950, the monomer layer can be cured such asusing an ultraviolet treatment provided by the curing module, such as toprovide a mura-free OTFE layer.

The substrate support techniques mentioned in relation to FIGS. 4A and4B are generally referred to in the context of the curing module orprinting system. However, such techniques can also be used such as inrelation to an end effector configuration for a handler robot configuredto manipulate the substrate. For example, a handler robot can include anend effector configuration such as to provide support for a substratewhile avoiding non-uniform direct physical contact with active regionson a first side of the substrate, or corresponding portions of a secondside of the substrate opposite the first side.

FIG. 5 illustrates generally an example of a diagram illustrating aportion of an ultraviolet treatment system that can be used inmanufacturing a light emitting device. The example of FIG. 5 can includeapparatus or can include using techniques that can be combined otherexamples herein, such as those described above (e.g., to provide anorganic encapsulation layer fabrication system or other system forperforming processing of substrates, such as substrates including one ormore OLED devices). The system of FIG. 5 can include an enclosure havinga controlled environment, such as a non-reactive gas environment, suchas including a transfer module 1400. The transfer module can include ahandler 1411, such as coupled to an end effector 1422 to manipulate oneor more substrates such as a first substrate 4000A, second substrate4000B, or third substrate 4000C. As an illustrative example, the systemcan include a curing module 2302. The curing module can also be used forproviding holding of substrates, such as to facilitate an evolution of asubstrate from one processing state to another (e.g., for dispersal orflowing of the deposited material), or to provide buffering for queuingof substrates. Additionally, or alternatively, other processing modulescan providing holding or buffering capabilities. Theenvironmentally-controlled regions can include one or more of aspecified gas purity, temperature, or particulate level.

Gas within various regions of the example of FIG. 5 can be circulatedlaterally across a surface of a substrate such as to provide asubstantially laminar flow profile. Additionally, or instead, one ormore fan filter units (FFUs) such as an FFU 1500 can provide a top-downflow profile, such as recovering gas through one or more ducts such as aduct 5201. As in other examples, a temperature controller 5650 can becoupled to one or more other portions of the system, such as to a heatexchanger located on or within the FFU 1500. In this manner, atemperature within the transfer module 1400 (or other portions of thesystem) can be controlled. The system can include or can be coupled to agas purification system, such as including a gas controller 5600configured to monitor or control a gas purity level of the controlledenvironment. The modules such as a holding module or the curing module2302 can include separate gas purification loops, or such modules canshare a controlled environment and purification facilities with thetransfer module 1400.

The curing module 2302 can include one or more lamps such as anultraviolet lamp. Such lamps can be located within the curing module2302, or outside the chamber such as optically coupled to the chamberthrough a quartz (or other UV-transparent) window.

Generally, one or more of the substrates in the thermally-controlledregions can be supported by a chuck configuration such as including aplate, frame, or tray. As mentioned in other examples herein, such aplate, frame, or tray can include one or more retractable lift pins(e.g., a pin 2324). As in other examples, the one or more retractablepins or other mechanical support features can be located in regions atthe perimeter or between display devices on the substrate. Similarly, avacuum chuck can support the substrate. A vacuum chuck can be outfittedwith vacuum ports and a vacuum supply, which can be turned on and offcontrollably, so as to provide vacuum suction to the backside ofsubstrate during a processing operation to improve the stability of thesubstrate or the thermal contact between the substrate and the chuckduring that processing operation. In various examples, instead of vacuumchuck, a non-vacuum chuck can be provided and the substrate can be heldin place either primarily by gravity and friction, or primarily bymechanical clamping. Substrates can be placed or removed from variouspositions, such as using an end effector 1422 of a handler 1411.

One or more pins such as a lift pin can be used to elevate the substratefor access by the end effector, as described further below. As mentionedabove, the curing module 2302 can also be used to facilitate thedispersal or flow of the film layer deposited on the substrate, such asto achieve a more planar and uniform coating (e.g., an OEL layer printedusing a printing module), such as using one or more of gravity, rotationof the substrate, or using one or more vacuum ports to further planarizethe substrate during one or more of the holding, material flowing ordispersing, or curing operation. However, the present inventors haverecognized that using a vacuum chuck having large ports during one ormore of holding, material flowing or dispersal or ultraviolet treatmentcan lead to unwanted visible defects or “mura.” The configuration shownin FIG. 5 can help to facilitate production of an organic thin filmencapsulant layer while inhibiting or suppressing mura formation.

As mentioned in examples elsewhere herein, a source of ultravioletemission can be used such as to treat one or more layers deposited on asubstrate being fabricated. For example, ultraviolet emission can beused to polymerize or otherwise treat an organic layer deposited on thesubstrate, such as for use in one or more processes related tomanufacturing a flat panel display assembly, such as including an OLEDdisplay assembly. Similar to aspects of other examples described herein,the system of FIG. 5 can include one or more enclosed regions (e.g.,“cells” or chambers) such as first region 2301A, a second region 2301B,and an “Nth” region 2301N. For example, three regions can be included(e.g., as shown illustratively in FIG. 5), and in another example, othernumbers of regions can be included. The regions can be oriented in a“stacked” configuration along a vertical axis of the system, such asshown illustratively in FIG. 5.

In an illustrative example, such as after deposition of an organic layeron a substrate, a material flowing or dispersal operation can beperformed, such as to improve the planarization or uniformity of acoating. A duration of the material flowing or dispersal operation cangenerally be greater than a duration of an ultraviolet treatmentoperation. Accordingly, in one approach, respective holding modules canbe used, such as separate from the curing module 2302 and arranged in astacked configuration with each region configured to house a substrateas shown in FIG. 21A or 21B. In this approach, the material flowing ordispersal operation can proceed without restricting access or otherwisetying up a separate ultraviolet treatment region. However, as discussedin examples elsewhere herein, multiple ultraviolet sources can be used,such including user lower-cost sources. In this manner, a throughputimpact of idling an ultraviolet source need not preclude use of the same“cell” or region (e.g., 2301A through 2301N) for both a holdingoperation and ultraviolet treatment operation, because multiple regionsare configured to provide ultraviolet treatment, enhancing throughput.Such an approach can also provide redundancy of the ultraviolet sourcessuch that processing can continue even if a particular ultravioletsource fails or is undergoing maintenance. Yet another benefit to suchan approach is that the substrate can undergo a material flowing ordispersal operation to disperse or flow a printed organic layer (e.g.,to improve planarization or uniformity) and the substrate can betreated, such as receiving an ultraviolet treatment, without requiringmovement of the substrate from the cell.

In the example of FIG. 5, a first ultraviolet source 2310A (e.g., anultraviolet-emitting LED array) can provide ultraviolet emission 2328having a specified range of wavelengths to a first substrate 4000A. Theultraviolet emission can be coupled to an interior of the enclosedregion 2310A such as through a window 2310A (e.g., a quartz window or anassembly such as including a normalization filter, or other filters orcoatings). As in the example of FIG. 6, FIG. 7A, FIG. 7B, FIG. 8A, orFIG. 8B, the environment within the region 2301A can be controlled andcan be isolated from a housing containing the first ultraviolet source2310A. In the second enclosed region 2310B, the second substrate 4000Bcan be held for a specified duration, such as for material flowing ordispersal or to await availability of other processes. During thespecified holding duration, a second ultraviolet source 2310B can bedisabled.

In examples elsewhere herein, a chuck can be used, such as contacting atleast a portion of a substrate such as to one or more of convey,support, or retain the substrate. The present inventors have recognized,among other things, that for some operations or material systems, suchas in relation to providing for the flowing or dispersing a depositedorganic layer, visible defects can be induced in the display regions ofthe substrate 4000A when the substrate is supported in a non-uniformmanner. For example, pins, support frames, holes in the chuck associatedwith retracted lift-pins, or vacuum apertures in the chuck under thesubstrate 4000A can induce visible defects in a finished device as shownillustratively in FIGS. 15A and 15B.

Without being bound by theory, it is believed that such defects canresult from localized variations in thermal conductivity that can createlocal gradients in the temperature of the substrate 4000A during, forexample, a material flowing or dispersal operation or from electrostaticinteractions between the substrate 4000A and other portions of thesystem, such as can be influenced by contact between the substrate 4000Aand other portions of the system. In an example, a specified temperatureuniformity can be maintained in a local region of the substrate, forexample, such that deviation in temperature adjacent to or within thelocal region is limited. For example, a significant temperaturevariation across the substrate can be tolerated but such variation canhave a limited gradient such that the temperature does not varysignificantly over a small distance along the substrate. In this manner,abrupt changes in visible characteristics of the finished display can beavoided and such gradual changes are less likely to be noticed or evendetectable.

As mentioned elsewhere, in one approach, regions outside the emitting ordisplay region of the substrate can be used to support substrate 4000A(e.g., as shown illustratively in FIG. 13A, FIG. 13B, or FIG. 13C).However, because large portions of the substrate 4000A generally doinclude emitting regions or portions of the actual display region, itcan be impractical to support the substrate only at the periphery ofsuch regions because such support induces unacceptable mechanical forcesor stresses elsewhere across the substrate 4000A, which may eitherdistort or fracture the substrate 4000A.

Accordingly, the present inventors have also recognized that thesubstrate 4000A can be supported by a chuck 2320A, such as during anultraviolet treatment operation, such as at least in part using apressurized gas 2304A to provide a gas cushion. According to variousexamples, the substrate 4000A can be supported exclusively by acontrolled arrangement of the pressurized gas 2304A, such as to “float”the substrate 4000A. In another example, the substrate 4000A can besupported using a uniform vacuum region under active areas of thesubstrate or otherwise in areas where defects induced bynon-uniformities would be deemed unacceptable. Retractable lift pins canbe located in regions at the periphery of the substrate, or betweenactive regions such as to facilitate loading or unloading of thesubstrate, such as shown illustratively in FIG. 15A or 15B.

In another approach, the substrate 4000A can be supported by apressurized gas 2304A impinging on a first surface of the substrate4000A, and an opposing force can be provided such as by a mechanicalstop 2312 contacting an opposing face of the substrate 4000A or arrangedto contact the substrate at one or more locations laterally. Generally,in examples where a gas cushion is used to the support the substrate,the substrate can be supported by a gas cushion provided between asurface of the substrate opposite the surface including the activeregions or the organic encapsulation layer, such as in a “face up”example where the organic encapsulation is on a top surface of thesubstrate and the gas cushion is provided on a bottom surface.

A second chuck 2320B can be provided as a portion of the second cell(e.g., the region 2301B), and an “Nth” chuck 2320N can be provided as aportion of the “Nth” cell (e.g., the region 2301N). Similarly, anelevating handler 1411 (or a handler robot as described in otherexamples herein) can include a table (or a corresponding end effector1422) including pressurized gas arrangement to support a substrate atleast in part using the pressurized gas. A conveyor 1430, or otherapparatus can also include such a pressurized gas arrangement, such thata substrate (e.g., a substrate 4000C) can be conveyed along a path 2440from a region 2101 elsewhere in the system (or external to the system)to a desired cell, such as the region 2301N. For example, one or more ofthe conveyer 1430, the effector 1422, or the first through “Nth” chucks2320A through 2320N can each define a “floatation zone.” In one or moreof the floatation zones, such as in a zone established by the firstchuck 2320A, an arrangement (e.g., an array) of ports such as a port2306A can be used to establish a gas cushion partially or entirelysupporting the substrate 4000A.

In examples where the substrate 4000A is supported exclusively by thegas cushion, a combination of positive gas pressure and vacuum can beapplied through the arrangement of ports. Such a zone having bothpressure and vacuum control can effectively provide a fluidic springbetween the chuck 2320A and a substrate. A combination of positivepressure and vacuum control can provide a fluidic spring withbidirectional stiffness. The gap that exists between the substrate(e.g., substrate 4000A) and a surface (e.g., the first chuck 2320A) canbe referred to as the “fly height,” and such a height can be controlledor otherwise established by controlling the positive pressure and vacuumport states. In this manner, the substrate orientation can be carefullycontrolled such as for one or more of a holding operation, a materialflowing or dispersing operation or an ultraviolet treatment operation.

Elsewhere, such as where the fly height need not be controlledprecisely, pressure-only floatation zones can be provided, such as alongthe conveyor 1430 or elsewhere. A “transition” zone can be provided suchas where a ratio of pressure to vacuum nozzles or area increases ordecreases gradually, such as along the conveyor 1430, along the table1422, or elsewhere. In an illustrative example, there can be anessentially uniform height between a pressure-vacuum zone, a transitionzone, and a pressure only zone, so that within tolerances, the threezones can lie essentially in one plane. A fly height of a substrate overpressure-only zones elsewhere can be greater than the fly height of asubstrate over a pressure-vacuum zone, such as in order to allow enoughheight so that a substrate will not collide with a floatation table inthe pressure-only zones. In an illustrative example, an OLED panelsubstrate can have a fly height of between about 150 micrometers (μ) toabout 300μ, above pressure-only zones, and then between about 30μ, toabout 50μ, above a pressure-vacuum zone. In an illustrative example, oneor more portions of the conveyor 1430, the table 1422, or the chucks2320A through 2320N can include an “air bearing” assembly provided byNewWay® Air Bearings (Aston, Pa., United States of America). While theexamples of gas pressurized support of a substrate are discussed inrelation to FIG. 5, such techniques can be used in addition to orinstead of other conveyance or support approaches, such as in relationother system examples described herein, and as discussed in relation toFIG. 19C.

In an example, mechanical retaining techniques, such as pins or a frame,can be used to restrict lateral translation of a substrate while thesubstrate is supported by a gas cushion. Such retaining techniques caninclude using spring loaded structures, such as to reduce theinstantaneous forces incident the sides of the substrate while thesubstrate is being retained; this can be beneficial as a high forceimpact between a laterally translating substrate and a retaining meanscan cause substrate chipping or even catastrophic breakage.

Each of the regions 2301A through 2301N can either share one or more gaspurification loops or can each be served by a respective gaspurification loop. Similarly, one or more FFUs can be located to providea laminar airflow parallel to a surface of substrate in each of theregions 2301A through 2301N. The regions 2301A through 2301N can eachinclude a valve or gate, such as to isolate the controlled environmentof each enclosed region 2301A through 2301N from the transfer module1400 or from each other. For example, the ultraviolet sources 2310Athrough 2310N need not be housed in enclosures isolated from theinterior of the regions 2301A through 2301N. Accordingly, such as duringmaintenance, a particular region can have its controlled environmentisolated from the rest of the enclosed regions using a valve or gate.

A temperature within the enclosed transfer module 1400 or within otherportions of the system can be controlled as described extensively inother examples herein, such as using a temperature controller 5650. Thetemperature controller 5650 can be coupled to the FFU 1500 or one ormore FFUs elsewhere. The temperature controller 5650 or other techniquescan be used such as to control a temperature of gas supplied by one ormore of the chucks 2320A through 2320N, the table 1422, or the conveyor1430. As mentioned in relation to FIG. 6, FIG. 7A, FIG. 7B, FIG. 8A, orFIG. 8B, one or more of the ultraviolet sources 2310A through 2310N canbe cooled using a liquid or circulating gas, such as including one ormore cooling loops isolated from other portions of the system.

FIG. 6 illustrates generally an example of a diagram illustrating anultraviolet treatment system that can be used in manufacturing a lightemitting device. The treatment system can be included as a portion ofother systems or techniques described herein, such as for use as acuring module (or, e.g., for use as a combination curing and holdingmodule). The ultraviolet treatment system can include an ultravioletsource assembly 912, such as configured to couple ultraviolet energy toa surface of a substrate 4000. As in other examples, a curing module8314 can include a controlled environment, such as provided by one ormore gas purification loops and coupled to one or more fan-filter-units(FFUs), such as to provide an environment having a specified maximumlevel of particulates or reactive contaminants.

The substrate 4000 can be loaded into the curing module 8314 or removedfrom the chamber 8314 such as using a handler 1410 and end effector1420, which can access the curing module 8314 from an adjacent transfermodule 1400, or through another chamber or assembly such as a load lock.A chuck 920 can be used to support the substrate 4000, such as usingphysical contact and vacuum to hold the substrate in place or using agas cushion arrangement as mentioned in other examples. One or more liftpins can be used, such as to elevate the substrate 4000 so that thesubstrate 4000 can be manipulated by the end effector 1420, such asshown illustratively in FIG. 15A or 15B.

An array of ultraviolet sources, such as sources 910A through 910N, canprovide ultraviolet energy, such as including a wavelength selected fromthe range of about 350 nanometers to about 400 nanometers. For example,a wavelength of about 385 nanometers or about 395 nanometers can beused. The sources can include a variety of configurations, such as usingrelatively small number of high-power sources as shown in the example ofFIG. 7A, or using an array of relatively lower-power sources, such asshown illustratively in FIG. 9, FIG. 10, or FIG. 11. The sources caninclude generally-available ultraviolet emitters, such asultraviolet-emitting light-emitting diodes (UV LEDs) or one or moremercury-based devices, such as one or more mercury arc sources.

In an example, a substrate or housing 918 of the ultraviolet sourceassembly 912 can be liquid or air-cooled. For example, a plenum 914 canbe provided, such as having one or more blowers such as a blower 915 toforce air across or through a portion of the ultraviolet source assembly912. Such a cooling loop can be separated from the controlledenvironment within the curing module 8314 or the transfer module 1400,for example. The environment surrounding the sources 910A through 910Ncan include the curing module 8314 controlled environment, or theenvironment surrounding the sources 910A through 910N can form aseparate enclosure, such as having a window 916 to allow ultravioletenergy to pass from the source enclosure to the curing module 8314. Inthis manner, maintenance of the source enclosure need not disturb thecontrolled environment within the curing module 8314.

As discussed in the examples below, the window 916 need not be uniformlytransmissive. For example, the window can include or can be coupled tooptics to converge, diverge, or collimate the ultraviolet energy. Inanother example, the window 916 can include transmission characteristicsthat vary in a specified manner over the area of the window, such as toinvert or otherwise compensate for a non-uniform power density ofdelivered ultraviolet energy in the plane of the substrate 4000, such aswithin a specified region of the substrate. In the example of FIG. 6,the window and the ultraviolet sources 910A through 910N are shown asarranged in a planar configuration, but other configurations arepossible, such as a cylindrical, parabolic, or spherical configuration.In an example the ultraviolet sources 910A through 910N can be used totreat one or more organic material layers to encapsulate an organiclight emitting diode (OLED) display device being fabricated as a portionof the substrate 4000. Such treatment generally includes providing aspecified dose of ultraviolet energy within a specified range ofwavelengths, and having a specified uniformity over a specified area ofthe substrate 4000.

A treatment process can generally be established in terms of a desireddose or dose-range of ultraviolet exposure, such as specified in termsof energy per unit area (e.g., Joules per square centimeter). Dose canbe calculated such as by multiplying incident power density by exposureduration. A trade-off can exist between intensity (e.g., incident power)and exposure duration. For example, a relatively high-power source canbe used and a desired UV dose can be achieved using a relatively shortexposure duration, which beneficially shortens processing time. However,such high-power UV irradiation may damage or degrade other portions ofthe display assembly, so a limit can exist as to the power densityprovided at the substrate by the ultraviolet source such as to avoidsuch damage or degradation.

As mentioned above, a uniformity of delivered ultraviolet energy canalso be controlled, such as to avoid variation in organic encapsulationlayer characteristics over a surface of the substrate 4000. In oneexample, such a uniformity can be specified in terms of incident poweror delivered UV dose, such as having a value of no more than 20%variation from highest to lowest incident power or dose over a specifiedcuring area of the substrate 4000, or having no more than 50% variationfrom highest to lowest incident power or dose over the specified curingarea of the substrate 4000, or having no more than 10% variation fromhighest to lowest incident power or dose over the specified curing areaof the substrate 4000.

Various UV source configurations can be used for the sources 910Athrough 910N. For example, a linear array or “bar” source can be used asshown in the configuration 8315 of FIG. 7A. Such a bar configuration caninclude a precision reflector, such as to focus or collimate theultraviolet energy in a direction towards the substrate 4000. In anotherexample, such a bar configuration can include one or more of a diffuseror transmissive filter, such as discussed in relation to other examplesherein.

A two-dimensional array configuration can be used, such as shownillustratively in the configurations 8316 through 8318 of FIG. 9, FIG.10, or FIG. 11. A sparse array of high-intensity sources can be used,such as can provide the power density illustrated in the example of FIG.12, such as including one or more reflectors. One or more of thesesource configurations can be mechanically fixed, or can be scannedacross a surface of the substrate. In such examples, either or both thesubstrate 4000 or the sources 910A through 910N can be scanned. Forexample, the sources 910A through 910N can be fixed, and the substrate4000 can be repositioned, such as to create a relative motion betweenthe substrate 4000 and the sources 910A through 910N to achievescanning.

FIG. 7A, FIG. 7B, FIG. 8A, and FIG. 8B illustrate generally examplesillustrating a portion of an ultraviolet treatment system 8315 that caninclude a linear array configuration 910 of ultraviolet sources such ascan be used in manufacturing a light emitting device. The linear array910 can be scanned in at least one axis to sweep a beam of ultravioletemission 922 across a specified region of the substrate 4000, such as ina region where a monomer has been deposited and is to be cured orotherwise treated with ultraviolet light. Such scanning can be achievedthrough either or both of repositioning the substrate 4000 or the lineararray 910, such as during ultraviolet treatment. A window 916 can beused, such as when the linear array 910 is located in an enclosureseparate from a chamber 8314 housing the substrate 4000. Such a window916 can include or can be coupled to one or more of optics or a filter,such as discussed below in relation to FIG. 12 or other examples.

The linear array 910 can offer an advantage of fewer ultraviolet sources(e.g., about 5 to about 10 LED sources, in an illustrative example).But, such a linear area 910 may result in additional system complexitywhere mechanical scanning is used to provide exposure to all of thespecified curing area of the substrate 4000. Mechanical scanning can besimplified in part by specifying that the linear array 910 is at leastas wide or as a long as one axis of the substrate, so that scanning isused only in the orthogonal axis (e.g., such axis as shown by arrows inFIGS. 7A and 8A). In this manner, an entire width or length of thesubstrate 4000 can be treated with UV radiation while scanning thelinear array 910 “gantry” only in a single axis, such as shownillustratively in FIG. 7A, FIG. 7B, FIG. 8A, and FIG. 8B. The lineararray 910 can include a precision reflector configuration, as mentionedabove. As an illustrative example, a high-power UV LED light barsupplying light at or near 395 nm wavelength is available from PhoseonTechnology (Hillsboro, Oreg., USA), such as including a reflectorconfiguration to enhance uniformity of a field illuminated by the lineararray 910. In addition or instead of such a precision reflector, one ormore of a filter or diffuser can be used, such as statically configurednearby the window 916 or included as a portion of the window 916. Inanother example, one or more of a filter or diffuser can be included asa portion of the linear array 910 assembly, such as mechanically scannedas a portion of the linear array 910. In an example, the power densitysupplied by the linear UV source is between 20 mW/cm² and 400 mW/cm².

The present inventors have also recognized that a uniformity ofultraviolet illumination can be compromised by degradation or failure ofone or more ultraviolet sources. In the illustrations of FIGS. 8A and8B, an optical sensor 917 such as an ultraviolet-sensitive photometercan be used to monitor the health of the linear array 910. For example,the optical sensor 917 can be mechanically scanned in an axis parallelto the linear array 910 so that information can be obtained regardingthe state of one or more optical sources included along the linear array910. In another example, the optical sensor 917 can include multiplesensors placed along an axis parallel to the linear array 910, such asobviating a need for mechanical scanning of the optical sensor 917.Other configurations of optical sensors can be used, such as mentionedin relation to other examples below. As in other examples discussedherein, one or more apertures can be provided in the chamber 8314, suchas to provide a mounting location for a fan or fan filter unit, or toprovide a location for an inlet or outlet of a non-reactive gas to beused within the chamber 8314, such as to facilitate coupling of a ductto the chamber 8314.

A linear array 910 source height from an upward-facing portion of thesubstrate 4000 can be represented by “H,” a relative velocity betweenthe optical energy emitted by the array 910 and the substrate can berepresented by “V.” The velocity can be established by moving one ormore of the array 910 relative to the substrate 4000 (e.g., scanning thearray mechanically) or the substrate 4000 relative to the array, such asby either floating the substrate on a cushion of gas or by moving achuck 920 supporting the substrate. An illuminated width can berepresented by “W,” with such a width increasing as H increases anddecreasing as H decreases. For dose modeling, a width of the array 910can be multiplied by the illuminated width W to estimate an area of thesubstrate 4000 irradiated by the array 910.

Generally, in view of the large scale of substrates 4000 that can beaccommodated by the examples described herein, throughput is aconsideration. Accordingly, one objective can be to provide anultraviolet dose in a manner that the appropriate dose is delivered in ashort or minimum amount of time, which can also reduce likelihood ofdamaging other portions of the substrate 4000 either through reducing orminimizing exposure to energy from the source, or merely throughreducing or minimizing the time during which the substrate is beingprocessed. However, a tradeoff can exist between various processingparameters such that the velocity, dose of energy, and source height Hare generally not arbitrarily established.

FIG. 9 illustrates generally an example of a diagram illustrating aportion of an ultraviolet treatment system that can include atwo-dimensional array configuration 8316 of ultraviolet sources 910Athrough 910N, such as can be used as a portion of an ultraviolettreatment system for treating a specified area of a substrate 4000. Bycontrast with the illustrative examples described in relation to FIG.7A, FIG. 7B, FIG. 8A, and FIG. 8B, a dense two-dimensional array oflow-power ultraviolet sources can be used. Such low-power sources caninclude low-power UV LEDs, which are generally more cost effective andreliable than mercury arc devices. Such low-power UV LEDs can also beused for large substrate 4000 geometries (e.g., exceeding 1 meter by 1meter), such as where high-power UV LEDs would become cost prohibitivedue to the large numbers of devices generally used to cover the largesubstrate 4000 area.

The dense array of hundreds of individual emitters can provide enhanceduniformity of delivered power at the substrate 4000 surface, as comparedto other approaches. Remaining non-uniformity can be addressed such asusing a diffuser plate or other filter or optics between the array 8316and the substrate 4000. As in the example of FIG. 8A or 8B, degradationor failure of one or more of the ultraviolet sources 910A through 910Ncan result in a non-uniform ultraviolet exposure field. Such anon-uniform field can lead to visible defects or unwanted variations inone or more layers of the substrate 4000. Accordingly, one or moreoptical sensors 917A through 917N (e.g., photometric sensors) can beused to sense such degradation or failure. As shown in the illustrationof FIG. 9, each of the optical sensors 917A through 917N can, but neednot, be aligned to provide a 1:1 correspondence to an optical source ina particular row or column and a corresponding optical sensor position,so that a failure of an individual optical source can be detected. Inanother approach, a spatially-averaged or spatially-cumulative specifiedintensity can be used as a go/no criterion, and fewer sensors can beused. A failure of an individual optical source can reduce an averageintensity or a cumulative intensity detected at one or more of theoptical sensors, such as triggering repair or replacement of the opticalsource array or otherwise halting further processing.

For example, one or more of the array 8316 of ultraviolet sources 910Athrough 910N or the optical sensors 917A can be mechanically scanned,such as to sample the output of the ultraviolet sources 910A through910N. In the event of a detected degradation or failure, furtherprocessing can be halted until the array 8316 is repaired or replaced.In an example, the array 8316 can include redundant sources amongst thesources 910A through 910N. In the event of degradation or failure, useof a combination of one or more defective sources can be suppressed, anda combination of other redundant ultraviolet sources can be usedinstead.

FIG. 10 illustrates generally an example of a two-dimensional arrayconfiguration 8317 of UV LED sources 1710A through 1710N, such as can beused as a portion of an ultraviolet treatment system for treating aspecified area of a substrate 4000. The two-dimensional array 8317 shownin FIG. 10 can eliminate use of precision reflectors, since such anarray generally provides UV radiation in the desired direction withoutuse of large reflectors. Use of low-power UV LEDs can also allowprecision control of intensity (through duty cycle modulation or currentmodulation) and exposure duration, such as allowing duration control toa precision of about 20 milliseconds. A substrate 1718 of the array 8317can include a heat-sink material, such as to assist in coupling heataway from the individual sources 1710A through 1710N in the array 8317.The substrate 1718 can include or can be coupled to a structural supportframe. The individual sources 1710A through 1710N can each include alens structure, such as to provide a converging, diverging, orcollimated ultraviolet beam for each of the individual sources 1710Athrough 1710N.

FIG. 11 illustrates generally an example of a housing configuration 8318for an array of ultraviolet sources, such as can be included as aportion of an ultraviolet treatment system. The housing can includeforced air circulation, such as using one or more fans as indicated byapertures 1815A through 1815D. An array of UV LEDs, such as a UV LED1810A, can be included within a housing 1812. One or more alignment orsupport posts can be included, such as one or more of posts 1824Athrough 1824D.

FIG. 12 illustrates generally an illustrative example of an intensityplot 1900 showing a non-uniformity of delivered ultraviolet energycorresponding to a known distance from the UV sources and the substrate.Such an intensity plot can be used to establish an inverse ornormalization filter configuration. In one approach, such as shownillustratively in FIG. 7A, a small number of fixed high-power lamps canbe used along with a reflector, such as illuminating a desired curingarea of the substrate 4000. However, while mechanically simple, such anapproach can have drawbacks.

For example, in the illustrative example of FIG. 12, four high-powerLEDs are used to illuminate an area of about 0.650 meters by about 0.725meters. Such an approach can provide areas of relatively higher incidentpower, such as an area 1902, along with areas of relatively lowerincident power, such as in the center of the plot 1900. Uniformity canbe enhanced by increasing a density of sources, but at the cost of usinga greater number of individual high-power LEDs. The present inventorshave recognized, among other things, that information about an intensitymap such as shown in the plot 1900 can be used to establish an invertingfilter to provide a uniform intensity or power distribution over adesired cure area while still using a sparse array or relatively smallnumber of UV sources.

For example, the plot 1900 can be normalized to a least intense regionand then the plot 1900 can be inverted. The inverted representation canbe used to establish a transmissive filter whereby the least intenseregions of the plot 1900 have the least, less, or no filtering ascompared to other regions, and the more intense regions are filtered toreduce transmission of energy through the filter proportionally in thosemore intense regions and thereby level out their transmission to a valuesimilar to the least intense regions. In this manner, a uniform areaillumination can be achieved on the substrate. Such inversion andtransmission need not be continuously varying, and in some examples allareas can be filtered to some extent. In an example, a transmissivefilter can include a half-tone or other dithering pattern of opaquematerial (e.g., an array of dots or other regions) such as to provide arange of transmitted intensities across a surface of the filtercorresponding to the inverted intensity pattern of a UV source.

The transmissive filter can be included as a portion of a window asdiscussed in other examples, or can be coupled to a window. For example,an absorbing coating can be patterned on a flexible film or on a rigidmedium such as glass or quartz. In an illustrative example, thetransmissive filter is coupled to a quartz window or a transparentsupport plate at a specified location between the substrate 4000 and UVsources. In another illustrative example, the transmissive filter ispatterned on a film and structurally supported by a frame at a specifiedlocation between the substrate 4000 and the UV sources.

In another approach (or in combination with the transmissive filterapproach described above), a diffuser can be used to provide a moreuniform illumination field. A diffuser can be more efficient than atransmissive filter having optically opaque regions. This inefficiencyof a transmissive filter can occur because brighter regions in theillumination field (e.g., “hotspots”) are generally reflected orabsorbed (e.g., blocked) by the transmissive filter, such as to achieveuniformity of illumination of the substrate. By contrast, a diffuser canassist in providing more uniform illumination by redirection ofpropagating light using one or more of refraction, diffraction, orscattering, such as comprising a translucent material.

For example, the window region 916 in one or more of FIG. 7A, FIG. 7B,FIG. 8A, or FIG. 8B, or other examples herein, can include a diffusersuch as including a plate or film similar to the examples discussedabove in relation to the transmissive filter. For example, a diffusercan include a holographically-imprinted plate or film. Such a diffusercan be used in examples where the UV light source is static (e.g., anarray source as shown in FIG. 9, FIG. 10, or FIG. 11). Such a diffusercan also be used in examples where the UV light source is mechanicallyscanned relative to the substrate or vice versa (e.g., FIG. 7A, FIG. 7B,FIG. 8A, or FIG. 8B). Examples of diffusers can include one or morelight management films such as can be obtained from WaveFrontTechnology, Inc. (Paramount, Calif., United States of America), such ascan include a micro-diffuser including a holographically recordedsurface relief microstructure. Other diffuser technologies can be used,such as can include bead structures or prismatic structures, forexample. In another example, a homogenizing diffuser can be used, suchas available from Luminit, LLC (Torrance, Calif., United States ofAmerica).

Such a diffuser arrangement can provide a more space-efficient UVexposure apparatus, such as by eliminating large reflectors andcompressing a distance between individual UV sources (e.g., LEDs) andthe substrate, as compared to approaches where the UV sources aremounted with a large separation from the substrate, and large reflectorsare used to assist in collimating or otherwise providing a more uniformillumination field. In an illustrative example, a diffuser can provide atransmissive efficiency of greater than 80 percent, or greater than 90percent, such as to provide UV illumination having a field uniformity ofbetter than 15% (e.g, having a uniformity that does not vary more than15% in intensity from a lowest intensity portion of the specified regiondefining the field to a highest intensity portion of the specifiedregion defining the field).

FIG. 13A and FIG. 13B illustrate generally illustrative examples of achuck configuration 2420A that includes ports or grooves in contact witha substrate 4006A in FIG. 13A, such as during one or more of adeposition, holding, material flow or dispersal, or cure process, andcorresponding visible non-uniformities (e.g., “mura”) in a layer of thesubstrate in FIG. 13B. In the example of FIG. 13A, the chuck 2420A caninclude one or more of a groove 4008 (e.g., coupled to a vacuum orincluded for another purpose), a retracted lift pin 4016, a large vacuumport 4014, a vacuum groove 4012, or one or more other features. In anillustrative example, the chuck 2420A can be used to retain a substrate4006A during processing, such as during deposition of an organic thinfilm encapsulant, or during other operations such as providing for theflow or dispersal of a deposited encapsulant layer (e.g., to achieve amore uniform or planar coating), or during thermal or ultraviolettreatment of such an encapsulant layer. In FIG. 13B, a resulting layeruniformity on the substrate 4006A can exhibit visible defects such as adefect 4018 corresponding to the groove 4016, a defect 4026corresponding to the retracted lift pin 4016, a defect 4022corresponding to the vacuum groove 4012, and a defect 4024 correspondingto the vacuum port 4014. Such defects can manifest as rainbow-coloredinterference patterns that having varying color uniformity creatingvisible outlines of the shapes shown in FIG. 13B, or shadows wheredisplay brightness or color rendering or not consistent in such regions.Without being bound by theory, it is believed that such variations canbe caused at least in part by variations in the thermal environment incontact with the substrate 2420A, even if such variations occur inrelation to features contacting a side of the substrate (e.g., a backside) opposite the deposition side. As discussed above, the presentinventors have recognized, among other things, that such mura can besuppressed or inhibited using various s uniform support techniques suchas described below and elsewhere herein.

The use of uniform support techniques to suppress mura can alsobeneficially reduce other sources of degradation such as particulatecontamination. Such degradation can be driven at least in part byincorporation of chemically or electrically/optically contaminants intothe device structure, either within the bulk material of each film or atthe interfaces between layers in the overall device stack. Over timechemically active contaminants can trigger a chemical reaction in thefilm that degrades the film material. Such chemical reactions can occursimply as a function of time, absent any other triggers, or can betriggered by ambient optical energy or injected electrical energy, forexample. Electrically or optically active contaminants can createparasitic electrical or optical pathways for the electrical or opticalenergy introduced or generated in the device during operation. Suchpathways can result in suppression of light output, or generation ofincorrect light output (e.g., light output of the wrong spectrum.) Thedegradation or loss may manifest as failure of an individual OLEDdisplay elements, “black” spotting in portions of an array of OLEDelements, visible artifacts or loss of electrical or optical efficiency,or unwanted deviation in color rendering accuracy, contrast, orbrightness in various affected regions of the array of OLED elements.

FIG. 14A, FIG. 14B, FIG. 14C, and FIG. 14D include illustrative examplesdepicting various regions of a substrate, and corresponding fixturessuch as a chuck or end effector that can include one or more pressurizedgas ports, vacuum ports, or vacuum regions. As mentioned elsewhere, asubstrate 4000 can include a glass material or one or more othermaterials. Generally, for production of flat panel displays, thesubstrate 4000 can include either a single large display or two or moresmaller displays that can be singulated from the substrate 4000. In theillustrative example of FIG. 14A, four display regions 4002A, 4002B,4002C, and 4002D are shown. These can be referred to as “active” regionsor “emitting regions,” for example. Use of the term “active” in thisexample does not somehow imply that such regions are actually opticallyemissive during processing, but instead refers to regions that caninclude devices configured to emit light or regions that otherwise forman emissive or transmissive portion of a display that is visible to anend user. Generally, visible defects in the regions 4002A through 4002Dwill be deemed unacceptable by end users, and accordingly varioustechniques can be used such as to enhance a visible uniformity of theregions 4002A through 4002D. Other variations in panel configuration ofthe substrate 4000 are possible. For example, a substrate 4000 caninclude a single display or array of OLED devices. In other examples,the substrate 4000 can be divided up into two, four, or eight regions,such as establishing corresponding perimeters for support, or such ashaving corresponding distributed porous media regions as mentioned inother examples herein. For other manufacturing examples in which otheroptical, electrical, or optoelectronic devices are on the substrate andbeing coated, the definition of “active” can be adjusted to suitablyencompass the regions corresponding to those devices.

In an example where the substrate 4000 is supported by direct physicalcontact, support can be uniform within each of the display regions 4002Athrough 4002D and can be non-uniform within the region 4004, extendingaround the periphery of the substrate 4000 as a whole and extends intothe interior spaces between each of the display regions 4002A through4002D. Such a region 4004 can be referred to as a “keep out” area,indicating that emitting or active elements of the display should bekept clear of such non-uniform support regions (or vice versa). Forexample, one or more “lift pins” can be located in an area as shownillustratively in FIG. 14A, such as in a first region 2124A, a secondregion 2124B (e.g., in a location between display regions 4002A and4002B), and an “Nth” region 2124N, and after the substrate is loweredonto the chuck and such lift pins are therefore in the retractedposition, the hole into which the lift pin is retracted will represent agap region in the physical support of the substrate. Alternatively, orin addition, one or more of the locations in the array can insteadinclude a vacuum port, such as to retain the substrate in place and holdit flat and in level physical contact with the chuck surface. Forexample, one or more lift pins can be used to raise or lower thesubstrate relative to a chuck before or after processing, and one ormore vacuum ports can be used to retain the substrate during processing.

As in other examples, the substrate can be supported by a cushion ofgas. For example, in FIG. 14A, the chuck may comprise a continuous arrayof small pressure apertures, or a continuous porous plate, providing acontinuous flow of pressurized gas on which the substrate can float.Holes can still be provided in the chuck surface, such as 2124A and2124B, for example, for lift pins (which when retracted sit below thechuck surface), but because the substrate floats above the chucksurface, the presence of mura or non-uniformity in the coated over suchholes can be reduced or eliminated. In this way, even the interiorregions in between regions 4002A through 4002D may be utilized as activeregions, improve productivity and enabling the manufacture of a largercontinuous active device. As in yet other examples, a combination ofpressurized gas ports and vacuum ports can be used, such as shown in theillustrative example of FIGS. 14B through 14D. For example, in the topview of FIG. 14B or the side view of FIG. 14C, the substrate 4000 can beretained such as by one or more vacuum ports (e.g., circular ports, orslots, for example) such as in the regions 2124A through 2124N as shownin region 4004 of FIG. 14B. Such a region 4004 can again include aperiphery of a substrate 4000. In an illustrative example, physicalcontact between the substrate 4000 and any fixtures can generally berestricted to such a periphery region 4004 during certain processingoperations, such as during one or more of a deposition operation (e.g.,printing of a material on substrate 4000), a holding operation, amaterial flow or dispersal operation, or a heat or ultraviolet treatmentoperation. Such operations can be included as at least a portion of athin film encapsulation (TFE) process, where the substrate 4000 may besusceptible to creation of imperfections or visible defects

Such a region 4004 can, for example, extend inward from the edges of thesubstrate by 100 millimeters or 200 millimeters. Elsewhere, thesubstrate can be supported at least in part in the region 4002 using oneor more pressurized gas ports 2106A through 2106N. Such a combination ofvacuum ports and pressurized gas ports can avoid imparting undue stresson a large substrate 4000 because the substrate can be supportedphysically in the periphery region 4004, and supported at least in partby pressurized gas in the central region 4002. In this manner, it doesnot matter whether the substrate 4000 includes a single large displaybeing fabricated, or several smaller displays. Therefore, a commonfixture 2120 configuration can be used for a variety of differentdisplay configurations because such a fixture 2120 can restrict contactto the peripheral region 4004 of the substrate 4000 while supporting thesubstrate 4000 elsewhere (e.g., centrally) with pressurized gas. In anexample where the fixture 2120 serves as a chuck, one or more of theregions 2124A through 2124N can include a lift pin instead of a vacuumport, or in addition to a vacuum port, such as to lift the substrate4000 to allow clearance under the substrate for manipulation by ahandler. In addition, a flow of pressurized gas can be modulated at oneor more of the gas ports 2106A through 2106N, such as to assist insupporting or lifting the substrate for or during manipulation. Inanother approach, the combination of gas ports 2106A through 2106N canbe used to assist in “floating” the substrate for conveyance to otherequipment, as mentioned in other examples.

FIG. 14D illustrates generally that the combination of pressurized gasand vacuum ports need not be restricted to a static chuck configurationas shown in FIG. 14B. For example, an end effector of a handler caninclude a combination of pressurized gas ports 2106A through 2106N, andvacuum ports in the regions 2124A through 2124N. The side view of FIG.14C can also describe a side view of one of the “tines” of the forkedend effector configuration shown in FIG. 14D. Such an end effector canbe used to manipulate the substrate 4000 without physically contactingthe substrate 4000 in regions other than the region 4004.

Alternatively, or in addition to the examples above, a distributedvacuum region can be established such as aligned with one or more of theregions 4002A through 4002D or 4002 of FIGS. 14A through 14C, such asshown and discussed in the illustrative examples of FIGS. 15A and 15B,to assist in retaining and maintaining a planar configuration of thesubstrate 4000. As discussed below, such a distributed vacuum region caninclude using a porous material such as a carbon or ceramic material,sintered glass, or some other material such as can include a pore sizeof less than 1 micrometer or even less than 0.5 micrometers in diameter.Such a small pore size can suppress formation of visible mura that wouldotherwise be present if large vacuum ports were used in the regions4002A through 4002D, such as discussed in relation to FIGS. 14A and 14B,above, and elsewhere herein. In another example, such as mentioned inrelation to FIG. 5, a gas cushion established by a pressurized gas canbe used at least in part to support the substrate such as within thedisplay regions 4002A through 4002D, such as to avoid formation ofvisible defects during a holding, a material flow or dispersal operationor an ultraviolet treatment operation, or during other productionprocesses. Such an example is illustrated generally in FIGS. 16A and16B.

FIG. 15A and FIG. 15B illustrate generally illustrative examples of achuck configuration that can include a combination of one or moremechanical support pins and one or more vacuum regions. Similar to theexample of FIG. 14A, and other examples discussed elsewhere herein, achuck 2220 can include one or more mechanical support pins (e.g.,including an extended lift pin 2224A). The mechanical support pins caninclude an extended configuration and a retracted configuration, such asactuated pneumatically, hydraulically, or electrically. As discussed inrelation to FIG. 14A and elsewhere, the mechanical support pins can belocated in regions other than the active areas of one or more displays,in the case that substrate is supported via physical contact (whereas incontrast, one of the benefits of using a floatation support mechanism isthe ability to achieve mura free coatings even over lift pin holes). Inthe example of FIG. 15A, the mechanical support pins, including theextended lift pin 2224A, can illustrate generally an extendedconfiguration, such as displacing a substrate 4000 vertically. Such aconfiguration can allow a gap under the substrate 4000, such as toaccommodate manipulation of the substrate by one or more end effectors,such as forked end effector 1420. The end effector 1420 can includegrooves, slots, other features, or can otherwise be sized and shaped toavoid interference with one or more of the mechanical support pins whenthe pins are in the extended configuration.

After the substrate 4000 is manipulated into place, the one or moremechanical support pins can be retracted, such as to a location flush orbelow flush with a surface of the chuck 2220, such as shown in FIG. 15B,including a retracted lift pin 2224B. In some examples, the substrate4000 can be further processed without further retention or anchoring.However, during certain operations, such as during one or more ofdeposition, a holding operation, a material flow/dispersing operation,or other treatment (e.g., ultraviolet treatment) of an organicencapsulation layer (or other layers) on the substrate 4000, one or moreof vacuum ports or distributed vacuum regions can be used, such as toassist in maintaining the substrate in a planar configuration. Forexample, one or more distributed (e.g., porous) vacuum regions can beincluded as a portion of the chuck 2220, such as including regions2206A, 2206B, 2206C, and 2206D. Unlike larger vacuum ports, ormechanical support pins, such regions 2206A through 2206D can be locateddirectly below portions of the substrate 4000 where “active” or“emitting” regions are being fabricated. Such distributed vacuum regionscan reduce or suppress formation of visible defects in one or morelayers being deposited or otherwise formed on the substrate 4000,because such distributed vacuum regions avoid the abrupt changes inthermal characteristics (e.g., thermal conductivity) presented by othertypes of structures, such as discussed above in relation to FIGS. 13Aand 13B. Without being bound by theory, it is believed that the use ofthe chuck structures shown herein, such as a distributed vacuum regionprovided by a porous medium, can also enhance uniformity of a coating orfilm layer deposited on the substrate 4000 such as providing a uniformelectrostatic coupling or field between the substrate 4000 and theporous regions 2206A, 2206B, 2206C, and 2206D.

As mentioned above, in one approach mechanical features such as liftpins or vacuum ports can be confined to a region peripheral to active oremitting areas of individual displays included in the substrate 4006A.However, such an approach can have disadvantages. For example, ifprocessing equipment is to be used for multiple substrate shapes, sizes,and display configurations, tool change-outs of the chuck 2420A might benecessary depending on an arrangement of “keep out” regions. FIGS. 16Aand 16B, by contrast with FIGS. 13A and 13B, illustrate generallyexamples of a chuck 2420B configuration that includes ports configuredto establish a pressurized gas cushion to support a substrate 4006B inFIG. 16A, such as during one or more of a deposition, a holdingoperation, a material dispersing or flowing operation, or cure process,and a corresponding uniformity in the resulting substrate in FIG. 16B.In this approach, because the substrate 4006B is not required to contactthermally-non-uniform features of the chuck 2420B during variousprocesses, a substrate 4006B as shown in FIG. 16B can avoid the largeand highly-visible mura produced by the features shown FIG. 13A.Different port configurations can be used, such as having a first portdensity in the region 2406A, and a second port density in the region2406B. As mentioned in other examples herein, a fly height, “h” can beestablished such as by using a combination of vacuum and pressurized gasports, such as in the arrays of the regions 2406A and 2406B. Forexample, in each row of ports, the ports can alternate between beingassigned as a vacuum port or a pressurized gas port. In this manner,precise control of the height, h, can be established and the substrate4006B can be stabilized in the z-dimension with respect to the chucksurface. As in other examples herein, a combination of mechanicalanchoring and pressurized gas can also be used. For example, lateralmotion of the substrate 4006B (e.g., in a direction parallel a surfaceof the chuck) can be limited, such as by using one or more lateral stopsor bumpers.

FIGS. 16C and 16D, by contrast with FIGS. 13A and 13B, illustrategenerally examples of a chuck configuration that includes a porousmedium 1906, such as to establish a distributed vacuum (in FIG. 16C) ordistributed pressure during one or more of a deposition, a holdingoperation, a material dispersing or flowing operation, or curingprocess, such as providing uniformity in the resulting substrate asshown in FIG. 16E. As mentioned in relation to other examples herein, aporous medium 1906 “plate” such as coupled to or included as a portionof a chuck 2420C can provide a “distributed” vacuum to securely hold thesubstrate 4006C during processing, or a pressurized gas cushion tosupport the substrate 4006C, such as without using large apertures asshown in FIG. 13A, and providing a substrate 4006C as shown in FIG. 16Ehaving reduced or minimize the formation of mura or other visibledefects. As mentioned in relation to other examples herein, a porousmedium 1906 “plate” such as coupled to or included as portion of a chuck2420C can provide a “distributed” pressure to uniformly float thesubstrate 4006C during processing, such as without using individualapertures as shown in FIG. 16A.

A porous medium 1906 as mentioned in relation to FIG. 15A, 16C, 16D, orsimilar distributed pressure or vacuum regions as mentioned elsewhereherein, can be obtained such as from Nano TEM Co., Ltd. (Niigata,Japan), such as having physical dimensions specified to occupy anentirety of the substrate 4006C, or specified regions of the substratesuch as display regions or regions outside display regions. Such aporous medium can include a pore size specified to provide a desiredvacuum holding force over a specified area, while reducing oreliminating mura or other visible defect formation such as duringholding, curing, or material dispersal or flowing operations. Asmentioned above, without being bound by theory it is believed that useof a porous medium can enhance uniformity of a coating or film layer onthe substrate 4006C, such as by reducing or minimizing mura or othervisible defects associated with non-uniform thermal profile orelectrostatic field profiled across the surface of the substrate, or ona surface opposite the coating or film layer. Alternatively, a porousmedium can be coupled to a pneumatic supply, such as to provide a gascushion, or various porous media regions can be coupled to a pneumaticsupply and a vacuum supply, respectively, to provide a gas cushionhaving a controlled “fly height,” such as in one or more specified zonesas mentioned in FIG. 19C. When such porous medium is utilized to providea distributed vacuum to hold down the substrate on the chuck surface,the presence of holes for lift pins can still provide non-uniformity andcan therefore include placement of such holes so as to avoid impactingthe active regions of the substrate. When such porous medium is used toprovide a distributed pressure supply to float the substrate above thechuck surface, the presence of holes for lift pins (e.g., for retractedlift pins) need not cause non-uniformity, therefore making a greaterportion of the substrate area available for the active regions.

The chuck configurations discussed in the examples of FIG. 5, FIG. 6,FIG. 14A, FIG. 14B, FIG. 14C, FIG. 14D, FIG. 15A, FIG. 16A, 16C, 16D,and other examples herein can be used in a variety of operations. Forexample, such chuck configurations can be included as a portion of anenclosed printing module, a holding module, a transfer module, a curingmodule such as including one or more ultraviolet treatment regions, orin modules configured to perform a combination of such operations, suchas within an environment having specified particulate contaminationlevels and a specified reactive species contamination level.

As in other examples shown and described herein, one or more of themodules shown in the systems 1000A, 1000B, 3000A, or 3000B, or in otherexamples can include shared or dedicated gas purification and monitoringfacilities, temperature control facilities, or particulate controlfacilities. For example, each module can include one or more gaspurification loops, fan filter units, or temperature controllers. Acontrolled environment in a respective module can be contiguous (e.g.,fluidically coupled) to an adjacent module, or the modules can includecontrolled environments that can be isolated from one another, such asfor enhanced control of gas purity, temperature, particulate levels, ormaintenance of a particular module.

For redundancy or maintenance, such as systems can include valving orgates such as to isolate an environment in one or more modules from oneor more other modules, such as to facilitate maintenance of temperaturecontrol, gas purification, solvent abatement, or particulate controlsystems without requiring dumping or purging of the controlledenvironment contained in other modules, or without substantiallyaltering an environment contained in other modules.

An environment within or surrounding the fabrication systems discussedelsewhere in this document herein can include illumination selected toavoid or suppress degradation of the materials used in fabrication orthe devices being fabricated. Also, various examples described in thisdocument can refer to gas-filled enclosures, such as providing acontrolled environment having one or more of a specified temperature,impurity level, or particulate level.

According to various examples, different light sources can be used inlighting elements to illuminate interior portions of the systems shownand described herein or to illuminate other regions, such as forvisualization of portions of the system by operators or machine visionsystems. A number or a grouping of lighting elements can be selected ina variety of manners, for use within or surrounding the systems shownand described elsewhere herein. For example, one or more lightingelements can be mounted flat, or in an adjustable manner to provide avariety of lighting positions or illumination angles. The placement oflighting elements need not be limited to a ceiling location, and suchlighting elements can be located on other interior or exterior surfacesof the systems shown and described herein.

The lighting elements can comprise any number, type, or combination oflights, for example, halogen lights, white lights, incandescent lights,arc lamps, or light emitting diodes or devices (LEDs). In anillustrative example, a lighting element can include from 1 LED to about100 LEDs, from about 10 LEDs to about 50 LEDs, or greater than 100 LEDs.LED or other lighting devices can emit any color or combination ofcolors in the visible color spectrum, outside the visible colorspectrum, or a combination thereof.

Some materials that can be used in OLED device fabrication, such as in aprinting system, can be sensitive to some wavelengths of light.Accordingly, a wavelength of light for lighting elements installed in orused to illuminate an OLED fabrication system can be selected tosuppress or eliminate material degradation during processing. Forexample, a 4× cool white LED can be used, as can a 4× yellow LED, or anycombination thereof. An example of a 4× cool white LED can include partnumber LF1B-D4S-2THWW4 available from IDEC Corporation of Sunnyvale,Calif. An example of a 4× yellow LED can include part numberLF1B-D4S-2SHY6, also available from IDEC Corporation. LEDs or otherlighting elements can be positioned or hung from any position on anyinterior portion of a ceiling frame or on another surface of an OLEDfabrication system. Lighting elements are not limited to LEDs, and othertypes of lighting elements or combinations of lighting elements can beused.

FIG. 17 illustrates generally a schematic representation of a gaspurification scheme that can be used in relation to portions orentireties of one or more other examples described herein, such as toestablish or maintain an controlled environment in an enclosure housingfabrication equipment used in manufacturing a light emitting device(e.g., an OLED device). For example, a gas enclosure system 502 caninclude a gas enclosure assembly 100 (e.g., an enclosure having acontrolled environment), a gas purification loop 130 in fluidcommunication with the gas enclosure assembly 100, and a thermalregulation system 140 (e.g., as can be referred to as a temperaturecontroller in other examples herein).

The system 502 can include a pressurized gas recirculation system 300,which can supply gas for operating various devices, such as a substrateflotation table or other pressurized-gas devices, such as for an OLEDprinting system. The pressurized gas recirculation system 300 caninclude or use a compressor, a blower, or both. Additionally, the gasenclosure system 502 can have a circulation and filtration systeminternal to gas enclosure system 502 (e.g., one or more fan filter units(FFUs) as described in other examples herein).

One or more ducts or baffles can separate non-reactive gas circulatedthrough the gas purification loop 130 from the non-reactive gas that isotherwise filtered and circulated internally for various embodiments ofa gas enclosure assembly. For example, the gas purification loop 130 caninclude an outlet line 131 from the gas enclosure assembly 100. Asolvent removal component 132 can be provided, for solvent abatement,and gas to be purified can be routed from the solvent removal component132 to a gas purification system 134. Gas purified of solvent and otherreactive gas species, such as one or more of ozone, oxygen, and watervapor, can be circulated back to the gas enclosure assembly 100, such asthrough an inlet line 133.

The gas purification loop 130 can include appropriate conduits andconnections such as to interface with monitoring or control devices. Forexample, ozone, oxygen, water vapor, or solvent vapor sensors can beincluded. A gas circulating unit, such as a fan, blower, or otherarrangement, can be separately provided or integrated, for example, ingas purification system 134, such as to circulate gas through the gaspurification loop 130. In the illustration of FIG. 17, the solventremoval component 132 and gas purification system 134 are shown asseparate units. However, the solvent removal component 132 and gaspurification system 134 can be housed together as a single unit.

The gas purification loop 130 of FIG. 17 can have solvent removalcomponent 132 placed upstream of gas purification system 134, so thatgas circulated from gas enclosure assembly 100 can pass through solventremoval component 132, such as via an outlet line 131. In an example,the solvent removal component 132 can include a solvent trapping systembased on adsorbing solvent vapor from a gas passing through the solventremoval component 132. For example, a bed or beds of a sorbent, such asactivated charcoal, molecular sieves, or the like, can effectivelyremove a wide variety of organic solvent vapors. In another example, acold trap technology can be used to remove solvent vapors as a portionof the solvent removal component 132. Sensors, such as ozone, oxygen,water vapor and solvent vapor sensors, can be used to monitor theremoval of such species from gas continuously circulating through a gasenclosure system, such as gas enclosure system 502. For example,information obtained from such sensors or other devices can indicatewhen sorbent, such as activated carbon, molecular sieves, or the like,have reached capacity or have otherwise become less effective, so thatthe bed or beds of sorbent can be regenerated or replaced, for example.

Regeneration of a molecular sieve can involve heating the molecularsieve, contacting the molecular sieve with a forming gas, a combinationthereof, or the like. For example, molecular sieves configured to trapvarious species, including ozone, oxygen, water vapor, or solvents, canbe regenerated by heating and exposure to a forming gas. In anillustrative example, such a forming gas can include hydrogen, forexample, a forming gas comprising about 96% nitrogen and about 4%hydrogen, with said percentages being by volume or by weight. Physicalregeneration of activated charcoal can be done using a procedure ofheating under a controlled environment.

A portion of the gas purification system 134 of the gas purificationloop 130 can include systems available, for example, from MBRAUN Inc.,of Statham, N.H., or Innovative Technology of Amesbury, Mass. The gaspurification system 134 can be used to purify one or more gases in gasenclosure system 502, for example, to purify the entire gas atmospherewithin a gas enclosure assembly. As mention above, in order to circulategas through gas purification loop 130, the gas purification system 134can have a gas circulating unit, such as a fan or blower, for example. Agas purification system can be selected or configured depending on thevolume of the enclosure, which can define a volumetric flow rate formoving a non-reactive gas through a gas purification system. In anillustrative example, a gas enclosure system having a gas enclosureassembly can include a volume of about 4 cubic meters and a gaspurification system that can move about 84 cubic meters per hour can beused. In another illustrative example, a gas enclosure system having agas enclosure assembly can include a volume of about 10 cubic meters anda gas purification system that can move about 155 cubic meters per hourcan be used. In yet another illustrative example, a gas enclosureassembly having a volume of between about 52 to about 114 cubic meters,more than one gas purification system can be used.

Gas filters, dryers, or other purifying devices can be included in thegas purification system 134. For example, a gas purification system 134can include two or more purifying devices, such as in a parallelconfiguration or otherwise arranged such that one of the devices can betaken off line for maintenance and one or more other devices can be usedto continue system operation without interruption. For example, the gaspurification system 134 can comprise one or more molecular sieves, suchas at least a first molecular sieve and a second molecular sieve, suchthat, when one of the molecular sieves becomes saturated withimpurities, or otherwise is deemed not to be operating efficientlyenough, the system can switch to the other molecular sieve whileregenerating the saturated or non-efficient molecular sieve. A controlunit can be provided for determining the operational efficiency of eachmolecular sieve, for switching between operation of different molecularsieves, for regenerating one or more molecular sieves, or for acombination thereof. As previously mentioned, molecular sieves can beregenerated and reused.

The thermal regulation system 140 of FIG. 17 can include at least onechiller 142, which can have a fluid outlet line 141 for circulating acoolant into a gas enclosure assembly, and fluid inlet line 143 forreturning the coolant to the chiller. An at least one fluid chiller 142can be provided for cooling the gas atmosphere within gas enclosuresystem 502. For example, the fluid chiller 142 can deliver cooled fluidto heat exchangers within the enclosure, where gas can be passed over afiltration system internal the enclosure. At least one fluid chiller canalso be provided with gas enclosure system 502 to cool heat evolvingfrom an apparatus enclosed within gas enclosure system 502. In anillustrative example, a fluid chiller can also be provided for gasenclosure system 502 to cool heat evolving from an OLED printing system.The thermal regulation system 140 can include heat-exchange or Peltierdevices and can have various cooling capacities. For example, a chillercan provide a cooling capacity of from between about 2 kilowatts (kW) toabout 20 kW of capacity. According to various examples, the gasenclosure system 502 can have a plurality of fluid chillers that canchill one or more fluids. A fluid chiller can use various fluids as aheat transfer medium, for example, such as water, anti-freeze, arefrigerant, or combination thereof. Leak-free, locking connections canbe used in connecting the associated conduits and system components.

While the examples above mentioning cooling capacities and chillingapplications, the examples above can also be applied to applicationswhere including buffering of substrates in a controlled environment, orfor applications where circulating gas can be maintained at atemperature similar to other portions of the system, such as to avoidunwanted heat transfer from substrates being fabricated or to avoiddisruption of temperature uniformity across a substrate or betweensubstrates.

FIGS. 18A and 18B illustrate generally examples of a gas enclosuresystem for integrating and controlling non-reactive gas and clean dryair (CDA) sources such as can be used to establish the controlledenvironment referred to in other examples described elsewhere herein,and such as can include a supply of pressurized gas for use with afloatation table. FIGS. 19A and 19B illustrate generally examples of agas enclosure system for integrating and controlling non-reactive gasand clean dry air (CDA) sources such as can be used to establish thecontrolled environment referred to in other examples described elsewhereherein, and such as can include a blower loop to provide, for example,pressurized gas and at least partial vacuum for use with a floatationtable. FIG. 19C illustrates generally a further example of a system forintegrating and controlling one or more gas or air sources, such as toestablish floatation control zones included as a portion of a floatationconveyance system.

Various examples described herein include enclosed modules that can beenvironmentally-controlled. Enclosure assemblies and correspondingsupport equipment can be referred to as a “gas enclosure system” andsuch enclosure assemblies can be constructed in a contoured fashion thatreduces or minimizes an internal volume of a gas enclosure assembly, andat the same time provides a working volume for accommodating variousfootprints of OLED fabrication system components, such as the deposition(e.g., printing), holding, loading, or treatment modules describedherein. For example, a contoured gas enclosure assembly according to thepresent teachings can have a gas enclosure volume of between about 6 m³to about 95 m³ for various examples of a gas enclosure assembly of thepresent teachings covering, for example, substrate sizes from Gen 3.5 toGen 10. Various examples of a contoured gas enclosure assembly accordingto the present teachings can have a gas enclosure volume of, forexample, but not limited by, of between about 15 m³ to about 30 m³,which might be useful for OLED printing of, for example, Gen 5.5 to Gen8.5 substrate sizes or other substrate sizes. Various examples of anauxiliary enclosure can be constructed as a section of gas enclosureassembly and readily integrated with gas circulation and filtration, aswell as purification components to form a gas enclosure system that cansustain a controlled, substantially low-particle environment forprocesses requiring such an environment.

As shown in FIG. 18A and FIG. 19A, various examples of a gas enclosuresystem can include a pressurized non-reactive gas recirculation system.Various examples of a pressurized gas recirculation loop can utilize acompressor, a blower and combinations thereof. According to the presentteachings, several engineering challenges were addressed in order toprovide for various examples of a pressurized gas recirculation systemin a gas enclosure system. First, under typical operation of a gasenclosure system without a pressurized non-reactive gas recirculationsystem, a gas enclosure system can be maintained at a slightly positiveinternal pressure (e.g., above atmospheric pressure) relative to anexternal pressure in order to safeguard against outside gas or air fromentering the interior should any leaks develop in a gas enclosuresystem. For example, under typical operation, for various examples of agas enclosure system of the present teachings, the interior of a gasenclosure system can be maintained at a pressure relative to thesurrounding atmosphere external to the enclosure system, for example, ofat least 2 mbarg, for example, at a pressure of at least 4 mbarg, at apressure of at least 6 mbarg, at a pressure of at least 8 mbarg, or at ahigher pressure.

Maintaining a pressurized gas recirculation system within a gasenclosure system can be challenging, as it presents a dynamic andongoing balancing act regarding maintaining a slight positive internalpressure of a gas enclosure system, while at the same time continuouslyintroducing pressurized gas into a gas enclosure system. Further,variable demand of various devices and apparatuses can create anirregular pressure profile for various gas enclosure assemblies andsystems of the present teachings. Maintaining a dynamic pressure balancefor a gas enclosure system held at a slight positive pressure relativeto the external environment under such conditions can provide for theintegrity of an ongoing OLED fabrication process. For various examplesof a gas enclosure system, a pressurized gas recirculation systemaccording to the present teachings can include various examples of apressurized gas loop that can utilize at least one of a compressor, anaccumulator, and a blower, and combinations thereof. Various examples ofa pressurized gas recirculation system that include various examples ofa pressurized gas loop can have a specially designed pressure-controlledbypass loop that can provide internal pressure of a non-reactive gas ina gas enclosure system of the present teachings at a stable, definedvalue. In various examples of a gas enclosure system, a pressurized gasrecirculation system can be configured to re-circulate pressurized gasvia a pressure-controlled bypass loop when a pressure of a gas in anaccumulator of a pressurized gas loop exceeds a pre-set thresholdpressure. The threshold pressure can be, for example, within a rangefrom between about 25 psig to about 200 psig, or more specificallywithin a range of between about 75 psig to about 125 psig, or morespecifically within a range from between about 90 psig to about 95 psig.In that regard, a gas enclosure system of the present teachings having apressurized gas recirculation system with various examples of aspecially designed pressure-controlled bypass loop can maintain abalance of having a pressurized gas recirculation system in anhermetically sealed gas enclosure.

According to the present teachings, various devices and apparatuses canbe disposed in the interior of a gas enclosure system and in fluidcommunication with various examples of a pressurized gas recirculationsystem. For various examples of a gas enclosure and system of thepresent teachings, the use of various pneumatically operated devices andapparatuses can provide low-particle generating performance, as well asbeing low maintenance. Exemplary devices and apparatuses that can bedisposed in the interior of a gas enclosure system and in fluidcommunication with various pressurized gas loops can include, forexample, but not limited by, one or more of a pneumatic robot, asubstrate floatation table, an air bearing, an air bushing, a compressedgas tool, a pneumatic actuator, and combinations thereof. A substratefloatation table, as well as air bearings can be used for variousaspects of operating an OLED printing system in accordance with variousexamples of a gas enclosure system of the present teachings. Forexample, a substrate floatation table utilizing air-bearing technologycan be used to transport a substrate into position in a printheadchamber, as well as to support a substrate during an OLED printingprocess.

For example, as shown in FIG. 18A, FIG. 18B, FIG. 19A, and FIG. 19B,various examples of gas enclosure system 503 and gas enclosure system504 can have external gas loop 3200 for integrating and controlling anon-reactive gas source 3201 and clean dry air (CDA) source 3203 for usein various aspects of operation of gas enclosure system 503 and gasenclosure system 504. Gas enclosure system 503 and gas enclosure system504 can also include various examples of an internal particle filtrationand gas circulation system, as well as various examples of an externalgas purification system, as previously described. Such examples of a gasenclosure system can include a gas purification system for purifyingvarious reactive species from a gas. Some commonly used non-limitingexamples of a non-reactive gas can include nitrogen, any of the noblegases, and any combination thereof. Various examples of a gaspurification system according to the present teachings can maintainlevels for each species of various reactive species, including variousreactive atmospheric gases, such as water vapor, oxygen, ozone, as wellas organic solvent vapors at 1000 ppm or lower, for example, at 100 ppmor lower, at 10 ppm or lower, at 1.0 ppm or lower, or at 0.1 ppm orlower. In addition to external loop 3200 for integrating and controllinggas source 3201 and CDA source 3203, gas enclosure system 503 and gasenclosure system 504 can have compressor loop 3250, which can supply gasfor operating various devices and apparatuses that can be disposed inthe interior of gas enclosure system 503 and gas enclosure system 504. Avacuum system 3270 can be also be provided, such as in communicationwith gas enclosure assembly 1005 through line 3272 when valve 3274 is inan open position.

Compressor loop 3250 of FIG. 18A can include compressor 3262, firstaccumulator 3264 and second accumulator 3268, which are configured to bein fluid communication. Compressor 3262 can be configured to compressgas withdrawn from gas enclosure assembly 1005 to a desired pressure. Aninlet side of compressor loop 3250 can be in fluid communication withgas enclosure assembly 1005 via gas enclosure assembly outlet 3252through line 3254, having valve 3256 and check valve 3258. Compressorloop 3250 can be in fluid communication with gas enclosure assembly 1005on an outlet side of compressor loop 3250 via external gas loop 3200.Accumulator 3264 can be disposed between compressor 3262 and thejunction of compressor loop 3250 with external gas loop 3200 and can beconfigured to generate a pressure of 5 psig or higher. Secondaccumulator 3268 can be in compressor loop 3250 for providing dampeningfluctuations due to compressor piston cycling at about 60 Hz. Forvarious examples of compressor loop 3250, first accumulator 3264 canhave a capacity of between about 80 gallons to about 160 gallons, whilesecond accumulator can have a capacity of between about 30 gallons toabout 60 gallons. According to various examples of gas enclosure system503, compressor 3262 can be a zero ingress compressor. Various types ofzero ingress compressors can operate without leaking atmospheric gasesinto various examples of a gas enclosure system of the presentteachings. Various examples of a zero ingress compressor can be runcontinuously, for example, during an OLED fabrication process utilizingthe use of various devices and apparatuses requiring compressed gas.

Accumulator 3264 can be configured to receive and accumulate compressedgas from compressor 3262. Accumulator 3264 can supply the compressed gasas needed in gas enclosure assembly 1005. For example, accumulator 3264can provide gas to maintain pressure for various components of gasenclosure assembly 1005, such as, but not limited by, one or more of apneumatic robot, a substrate floatation table, an air bearing, an airbushing, a compressed gas tool, a pneumatic actuator, and combinationsthereof. As shown in FIG. 18A for gas enclosure system 503, gasenclosure assembly 1005 can have an OLED printing system 2000 enclosedtherein. As schematically depicted in FIG. 18A, printing system 2000 canbe supported by printing system base 2150, which can be a granite stage.Printing system base 2150 can support a substrate support apparatus,such as a chuck, for example, but not limited by, a vacuum chuck, asubstrate floatation chuck having pressure ports, and a substratefloatation chuck having vacuum and pressure ports. In various examplesof the present teachings, a substrate support apparatus can be asubstrate floatation table, such as substrate floatation table printingregion 2250. Substrate floatation table printing region 2250 can be usedfor the frictionless support of a substrate. In addition to alow-particle generating floatation table, for frictionless Y-axisconveyance of a substrate, printing system 2000 can have a Y-axis motionsystem utilizing air bushings.

Additionally, printing system 2000 can have at least one X,Z-axiscarriage assembly with motion control provided by a low-particlegenerating X-axis air bearing assembly. Various components of alow-particle generating motion system, such as an X-axis air bearingassembly, can be used in place of, for example, variousparticle-generating linear mechanical bearing systems. For variousexamples of a gas enclosure and system of the present teachings, the useof a variety of pneumatically operated devices and apparatuses canprovide low-particle generating performance, as well as being lowmaintenance. Compressor loop 3250 can be configured to continuouslysupply pressurized gas to various devices and apparatuses of gasenclosure system 503. In addition to a supply of pressurized gas,substrate floatation table printing region 2250 of inkjet printingsystem 2000, which utilizes air bearing technology, also utilizes vacuumsystem 3270, which is in communication with gas enclosure assembly 1005through line 3272 when valve 3274 is in an open position.

A pressurized gas recirculation system according to the presentteachings can have pressure-controlled bypass loop 3260 as shown in FIG.18A for compressor loop 3250, which acts to compensate for variabledemand of pressurized gas during use, thereby providing dynamic balancefor various examples of a gas enclosure system of the present teachings.For various examples of a gas enclosure system according to the presentteachings, a bypass loop can maintain a constant pressure in accumulator3264 without disrupting or changing the pressure in enclosure 1005.Bypass loop 3260 can have first bypass inlet valve 3261 on an inlet sideof bypass loop, which is closed unless bypass loop 3260 is used. Bypassloop 3260 can also have back pressure regulator 3266, which can be usedwhen second valve 3263 is closed. Bypass loop 3260 can have secondaccumulator 3268 disposed at an outlet side of bypass loop 3260. Forexamples of compressor loop 3250 utilizing a zero ingress compressor,bypass loop 3260 can compensate for small excursions of pressure thatcan occur over time during use of a gas enclosure system. Bypass loop3260 can be in fluid communication with compressor loop 3250 on an inletside of bypass loop 3260 when bypass inlet valve 3261 is in an openedposition. When bypass inlet valve 3261 is opened, gas shunted throughbypass loop 3260 can be recirculated to the compressor if gas fromcompressor loop 3250 is not in demand within the interior of gasenclosure assembly 1005. Compressor loop 3250 is configured to shunt gasthrough bypass loop 3260 when a pressure of the gas in accumulator 3264exceeds a pre-set threshold pressure. A pre-set threshold pressure foraccumulator 3264 can be from between about 25 psig to about 200 psig ata flow rate of at least about 1 cubic feet per minute (cfm), or frombetween about 50 psig to about 150 psig at a flow rate of at least about1 cubic feet per minute (cfm), or from between about 75 psig to about125 psig at a flow rate of at least about 1 cubic feet per minute (cfm)or between about 90 psig to about 95 psig at a flow rate of at leastabout 1 cubic feet per minute (cfm).

Various examples of compressor loop 3250 can utilize a variety ofcompressors other than a zero ingress compressor, such as a variablespeed compressor or a compressor that can be controlled to be in eitheran on or off state. As previously discussed herein, a zero ingresscompressor ensures that no atmospheric reactive species can beintroduced into a gas enclosure system. As such, any compressorconfiguration preventing atmospheric reactive species from beingintroduced into a gas enclosure system can be utilized for compressorloop 3250. According to various examples, compressor 3262 of gasenclosure system 503 can be housed in, for example, but not limited by,an hermetically-sealed housing. The housing interior can be configuredin fluid communication with a source of gas, for example, the same gasthat forms the gas atmosphere for gas enclosure assembly 1005. Forvarious examples of compressor loop 3250, compressor 3262 can becontrolled at a constant speed to maintain a constant pressure. In otherexamples of compressor loop 3250 not utilizing a zero ingresscompressor, compressor 3262 can be turned off when a maximum thresholdpressure is reached, and turned on when a minimum threshold pressure isreached.

In FIG. 19A for gas enclosure system 504, blower loop 3280 utilizingvacuum blower 3290 is shown for the operation of substrate floatationtable printing region 2250 of inkjet printing system 2000, which arehoused in gas enclosure assembly 1005. As previously discussed hereinfor compressor loop 3250, blower loop 3280 can be configured tocontinuously supply pressurized gas to a substrate floatation tableprinting region 2250 of printing system 2000.

Various examples of a gas enclosure system that can utilize apressurized gas recirculation system can have various loops utilizing avariety of pressurized gas sources, such as at least one of acompressor, a blower, and combinations thereof. In FIG. 19A for gasenclosure system 504, compressor loop 3250 can be in fluid communicationwith external gas loop 3200, which can be used for the supply of gas forhigh consumption manifold 3225, as well as low consumption manifold3215. For various examples of a gas enclosure system according to thepresent teachings as shown in FIG. 19A for gas enclosure system 504,high consumption manifold 3225 can be used to supply gas to variousdevices and apparatuses, such as, but not limited by, one or more of asubstrate floatation table, a pneumatic robot, an air bearing, an airbushing, and a compressed gas tool, and combinations thereof. Forvarious examples of a gas enclosure system according to the presentteachings, low consumption 3215 can be used to supply gas to variousapparatuses and devises, such as, but not limited by, one or more of anisolator, and a pneumatic actuator, and combinations thereof.

For various examples of gas enclosure system 504 of FIGS. 19A and 19B, ablower loop 3280 can be utilized to supply pressurized gas to variousexamples of substrate floatation table printing region 2250. In additionto a supply of pressurized gas, substrate floatation table printingregion 2250 of OLED inkjet printing system 2000, which utilizes airbearing technology, also utilizes blower vacuum 3290, which is incommunication with gas enclosure assembly 1005 through line 3292 whenvalve 3294 is in an open position. Housing 3282 of blower loop 3280 canmaintain first blower 3284 for supplying a pressurized source of gas tosubstrate floatation table printing region 2250, and second blower 3290,acting as a vacuum source for substrate floatation table printing region2250, which is housed in a gas environment in gas enclosure assembly1005. Attributes that can make blowers suitable for use as a source ofeither pressurized gas or vacuum for various examples a substratefloatation table include, for example, but not limited by, that theyhave high reliability; making them low maintenance, have variable speedcontrol, and have a wide range of flow volumes; various examples capableof providing a volume flow of between about 100 m³/h to about 2,500m³/h. Various examples of blower loop 3280 additionally can have firstisolation valve 3283 at an inlet end of blower loop 3280, as well ascheck valve 3285 and a second isolation valve 3287 at an outlet end ofblower loop 3280. Various examples of blower loop 3280 can haveadjustable valve 3286, which can be, for example, but not limited by, agate, butterfly, needle or ball valve, as well as heat exchanger 3288for maintaining gas from blower loop 3280 to substrate floatation tableprinting region 2250 at a defined temperature.

FIG. 19A depicts external gas loop 3200, also shown in FIG. 18A, forintegrating and controlling gas source 3201 and clean dry air (CDA)source 3203 for use in various aspects of operation of gas enclosuresystem 503 of FIG. 18A and gas enclosure system 504 of FIG. 19A.External gas loop 3200 of FIG. 18A and FIG. 19A can include at leastfour mechanical valves. These valves include first mechanical valve3202, second mechanical valve 3204, third mechanical valve 3206, andfourth mechanical valve 3208. These various valves are located atpositions in various flow lines that allow control of both anon-reactive gas and an air source such as clean dry air (CDA).According to the present teachings, a non-reactive gas can be any gasthat does not undergo a chemical reaction under a defined set ofconditions. Some commonly used non-limiting examples of non-reactive gascan include nitrogen, any of the noble gases, and any combinationthereof. From a house gas source 3201, a house gas line 3210 extends.House gas line 3210 continues to extend linearly as low consumptionmanifold line 3212, which is in fluid communication with low consumptionmanifold 3215. A cross-line first section 3214 extends from a first flowjuncture 3216, which is located at the intersection of house gas line3210, low consumption manifold line 3212, and cross-line first section3214. Cross-line first section 3214 extends to a second flow juncture3218. A compressor gas line 3220 extends from accumulator 3264 ofcompressor loop 3250 and terminates at second flow juncture 3218. A CDAline 3222 extends from a CDA source 3203 and continues as highconsumption manifold line 3224, which is in fluid communication withhigh consumption manifold 3225. A third flow juncture 3226 is positionedat the intersection of a cross-line second section 3228, clean dry airline 3222, and high consumption manifold line 3224. Cross-line secondsection 3228 extends from second flow juncture 3218 to third flowjuncture 3226. Various components that are high consumption can besupplied CDA during maintenance, by means high consumption manifold3225. Isolating the compressor using valves 3204, 3208, and 3230 canprevent reactive species, such as ozone, oxygen, and water vapor fromcontaminating a gas within the compressor and accumulator.

By contrast with FIGS. 18A and 19A, FIGS. 18B and 19B illustrategenerally a configuration wherein a pressure of gas inside the gasenclosure assembly 1005 can be maintained within a desired or specifiedrange, such as using a valve coupled to a pressure monitor, P, where thevalve allows gas to be exhausted to another enclosure, system, or aregion surrounding the gas enclosure assembly 1005 using informationobtained from the pressure monitor. Such gas can be recovered andre-processed as in other examples described herein. As mentioned above,such regulation can assist in maintaining a slight positive internalpressure of a gas enclosure system, because pressurized gas is alsocontemporaneously introduced into the gas enclosure system. Variabledemand of various devices and apparatuses can create an irregularpressure profile for various gas enclosure assemblies and systems of thepresent teachings. Accordingly, the approach shown in FIGS. 18B and 19Bcan be used in addition or instead of other approaches described hereinsuch as to assist in maintaining a dynamic pressure balance for a gasenclosure system held at a slight positive pressure relative to theenvironment surrounding the enclosure.

FIG. 19C illustrates generally a further example of a system 505 forintegrating and controlling one or more gas or air sources, such as toestablish floatation control zones included as a portion of a floatationconveyance system. Similar to the examples of FIGS. 19A and 19B, FIG.19C illustrates generally a floatation table printing region 2250.Additionally shown in the illustrative example of FIG. 19C are an inputregion 2100 and an output region 2300. The regions 2100, 2200, 2300 arereferred to as input, printing, and output for illustration only. Suchregions can be used for other processing steps, such as conveyance of asubstrate, or support of a substrate such as during one or more ofholding, drying, or curing of the substrate in one or more othermodules. In the illustration of FIG. 19C, a first blower 3284A isconfigured to provide pressurized gas in one or more of the input oroutput regions 2100 or 2300 of a floatation table apparatus. Suchpressurized gas can be temperature controlled such as using a firstchiller 142A coupled to a first heat exchanger 1502A. Such pressurizedgas can be filtered using a first filter 1503A. A temperature monitor8701A can be coupled to the first chiller 142 (or other temperaturecontroller).

Similarly, a second blower 3284B can be coupled to the printing region2200 of the floatation table. A separate chiller 142B can be coupled toa loop including a second heat exchanger 1502B and a second filter1503B. A second temperature monitor 8701B can be used to provideindependent regulation of the temperature of pressurized gas provided bythe second blower 3284B. In this illustrative example, the input andoutput regions 2100 and 2300 are supplied with positive pressure, butthe printing region 2200 can include use of a combination of positivepressure and vacuum control to provide precise control over thesubstrate position. For example, using such a combination of positivepressure and vacuum control, the substrate can be exclusively controlledusing the floating gas cushion provided by the system 504 in the zonedefined by the printing region 2200. The vacuum can be established by athird blower 3290, such as also provided at least a portion of themake-up gas for the first and second blowers 3284A or 3284B within theblower housing 3282.

FIG. 20A, FIG. 20B, and FIG. 20C illustrate generally views of at leasta portion of a system, such as including a transfer module, that can beused in manufacturing an electronic device (e.g., an organic lightemitting diode (OLED) device). The controlled environment within variousenclosures of a system can include a controlled particulate level.Particulates can be reduced or minimized such as by using aircirculation units and filters, such as can be referred to as fan filterunits (FFUs). An array of FFUs can be located along a path traversed bythe substrate during processing. The FFUs need not provide a down-flowdirection of air flow. For example, an FFU or ductwork can be positionedto provide a substantially laminar flow in a lateral direction across asurface of the substrate. Such laminar flow in the lateral direction canenhance or otherwise provide particulate control.

In the example of FIG. 20A, FIG. 20B, and FIG. 20C, one or more fanfilter units (FFUs), such as FFUs 1500A through 1500F can be used toassist in maintaining an environment within the transfer module 1400Ahaving a controlled level of particulates or contaminants. Ducting suchas first and second ducts 5201A or 5201B can be used, such as to providea return air pathway as shown in the down-flow examples of FIG. 20B andFIG. 20C. A controlled temperature can be maintained at least in partusing a temperature controller 8700, such as coupled to one or more heatexchangers 1502. One or more temperature monitors, such as a temperaturemonitor 8701, can be placed in specified locations (e.g., on or nearby asubstrate, such, or end effector) to provide feedback to assist inmaintaining a substrate or a region nearby a substrate within aspecified range of temperatures. In an example, as discussed below, thetemperature monitor can be a non-contact sensor, such as an infraredtemperature monitor configured to provide information indicative of asurface temperature sampled by the sensor. Other configurations arepossible, such as can include placing the heat exchanger within ornearby a return air duct in a lower portion of the chamber as shownillustratively in FIG. 21B.

In FIG. 20C, a circle denotes generally an outer dimensional limit ofsweep of the handler 1410, and the regions indicated in the corners canbe used as ducts 5201A, 5201B, 5201C, or 5201D, such as to provide areturn pathway for a purified gas (e.g., nitrogen) to be captured fromthe bottom of the transfer module 1400A and then recirculated orscrubbed, such as for reinjection through one or more FFUs 1500A through1500F located at the top of the transfer module 1400A.

FIG. 21A and FIG. 21B illustrate generally views of a portion of asystem, such as can include a stacked configuration of substrate 4000processing areas. A port of the processing module 1200 can include oneor more doors or hatches, such as a door 3301. For example, such doorscan be mechanically or electrically interlocked so that a dooraccessible to an exterior of a fabrication system is unable to be openedunless a corresponding door elsewhere on or within the system is closed.For example, the door 3301 can be used to perform maintenance, while theprocessing module 1200 is otherwise isolated from an inert environment,or a particulate or contaminant-controlled environment in other enclosedportions of a fabrication system.

As mentioned above, such a particulate or contaminant-controlledenvironment can be maintained at least in part using one or more FFUs1500. In the example of FIG. 21B, a cross-flow configuration is used,such as to maintain a substantially laminar flow of gas (e.g., anon-reactive gas) across each of one or more cells 3350 that can includea substrate. A heat exchanger 1502 can, but need not be located nearbyor as a portion of the FFU 1500. For example, the heat exchanger 1502can be located below a substrate handling area, such as included withinor as a portion of a return duct 5201. A temperature can be controlledby a temperature controller 8700, such as coupled to a temperaturesensor 8701. The curved profile of portions of the duct 5201 can bespecified at least in part using a computational fluid dynamicstechnique, such as to maintain specified flow characteristics (e.g.,laminar flow) within the processing module 1200.

In addition to queuing substrates (or instead of queuing substrates),such as until the next module is ready to receive such substrates, theprocessing module 1200 can functionally participate in the substratefabrication process, for example by providing drying functions, or byholding the substrate for a specified duration (or until specifiedcriteria are met) so as to allow the substrate to evolve from onecondition to another. In the case of holding for the purpose of evolvingthe substrate, for example, the substrate can be held so as to allow fora liquid to settle or flow. A temperature of the substrate during suchevolution can be controlled through the controlled application oftemperature controlled gas flow across the substrate surface, such aslaminar flow, which can be provided to flow across the plane of thesubstrate, as indicated in FIG. 21B.

In general, the holding module temperature need not be the same as thetemperature of the environment in or surrounding the other systemmodules, for example, the printing module or the substrate handlingmodule. In another example, the substrate can rest on a cushion oftemperature-controlled gas (similar to other examples described herein,such as where the substrate is supported using a floating cushion of gasfor one or more of printing, holding, or curing operations such a curingoperation including ultraviolet treatment).

In the case of drying a substrate in a processing module 1200, thecontrolled environment can provide for continuous removal of evaporatedvapors via a vapor trap or gas recirculation and purification system,and the dying process can be further controlled through the controlledapplication of gas flow across the substrate surface, such as laminarflow, which can be provided to flow across the plane of the substrate,as indicated in FIG. 21B. In an example, the processing module 1200includes a drying module, and other portions of a system can beconfigured to at least partially evacuate or purge an atmosphere withinthe drying module to facilitate a drying operation, such as after aprinting operation.

FIG. 22A illustrates generally a portion of a system, such as includinga transfer module coupled to other chambers or modules, that can be usedin manufacturing an electronic device (e.g., an organic light emittingdiode (OLED) device). FIG. 22B illustrates generally a handlerconfiguration that can be used, such as for manipulating a substratewithin the module shown in FIG. 12A.

As in the example of FIG. 20A, the transfer module 1400B can include oneor more fan filter units (FFUs), such as 1500A through 1500N (e.g., 14FFUs). FIG. 22B illustrates generally a handler 2732 configuration thatcan be used, such as for manipulating a substrate 4000 within the module1400B shown in FIG. 21A. By contrast with the handler 1410A of thetransfer module 1400A of FIG. 21A, the hander 1410B of FIG. 22Billustrates generally that a track 2734 or rail configuration can beused, such as to provide linear translation of the handler 2732 in anaxis. In this manner, a broad range of other chambers or modules can becoupled to the transfer module 1400B, such as in a clusteredconfiguration, without requiring that each other module or chamber becoupled in a manner radiating out from a single point. As in the exampleof FIG. 20C, one or more ducts can be located in portions of thetransfer module 1400B in a region outside the race-track shaped range ofmotion of the handler 1410B. For example, such locations can be used toprovide return ducts to bring a gas (e.g., nitrogen) from a lowerportion of the transfer module 1400B upwards to a plenum above the FFUarray as shown in other examples.

An end effector of the handlers shown in FIG. 20C or 22B can include auniform substrate support system similar to the various examples ofchuck and end effector configurations described elsewhere herein, suchas to facilitate formation of a mura-free organic encapsulation layer.

VARIOUS NOTES & EXAMPLES

Example 1 can include or use subject matter (such as an apparatus, amethod, a means for performing acts, or a device readable mediumincluding instructions that, when performed by the device, can cause thedevice to perform acts), such as can include or use a coating system forproviding a coating on a substrate, the system comprising an enclosedprinting system configured to deposit a patterned organic layer on asubstrate, the patterned organic layer coating at least a portion of alight-emitting device fabricated upon the substrate, an enclosed curingmodule including an ultraviolet treatment region configured toaccommodate a substrate and configured to provide an ultraviolettreatment to the patterned organic layer, and an enclosed substratetransfer module configured to receive the substrate from an atmosphericenvironment different from an environment of one or more of the enclosedprinting system or the enclosed curing module. In Example 1, thepatterned organic layer is to occupy a deposition region of thesubstrate on a first side of the substrate, and the enclosed curingmodule is configured to uniformly support the substrate in theultraviolet treatment region using a gas cushion, the gas cushionprovided to a second side of the substrate opposite the first side, thegas cushion established between the substrate and a chuck.

Example 2 can include, or can optionally be combined with the subjectmatter of Example 1, to optionally include a deposition region on thefirst side of the substrate that overlaps with an active region of thesubstrate comprising the light-emitting device, and wherein the gascushion is provided to the second side of the substrate opposite theactive region.

Example 3 can include, or can optionally be combined with the subjectmatter of Example 2, to optionally include a chuck configured to supportthe substrate using physical contact with the second side of thesubstrate, opposite the first side, where the physical contact is in anarea corresponding to a region outside the active region.

Example 4 can include, or can optionally be combined with the subjectmatter of one or any combination of Examples 1 through 3 to optionallyinclude a chuck that comprises a porous ceramic material, and whereinthe gas cushion is established by forcing gas through the porous ceramicmaterial to support the second side of the substrate above the porousceramic material.

Example 5 can include, or can optionally be combined with the subjectmatter of one or any combination of Examples 1 through 4 to optionallyinclude a gas cushion established using pressurized gas.

Example 6 can include, or can optionally be combined with the subjectmatter of one or any combination of Examples 1 through 5 to optionallyinclude a gas cushion that is established using a combination of apressurized gas region and at least a partial vacuum region.

Example 7 can include, or can optionally be combined with the subjectmatter of Example 6, to optionally include at least one of pressurizedgas or evacuated gas used to establish the gas cushion that is recoveredand recirculated.

Example 8 can include, or can optionally be combined with the subjectmatter of one or any combination of Examples 1 through 7 to optionallyinclude a patterned organic layer comprising at least a portion of anencapsulation structure, the substrate comprising a glass sheet andlight-emitting devices, the encapsulation structure established to sealat least a portion of the light-emitting devices from exposure toambient air against the glass sheet, and the enclosed curing moduleconfigured (1) to hold the substrate at rest for a duration fordispersal of the patterned organic layer to cover the light-emittingdevices, and (2) to provide the ultraviolet treatment without requiringfurther movement of the substrate between holding and ultraviolettreatment operations.

Example 9 can include, or can optionally be combined with the subjectmatter of one or any combination of Examples 1 through 8 to optionallyinclude an ultraviolet treatment region of the curing module comprisinga gantry-mounted ultraviolet (UV) source, the gantry configured totransport the UV source relative to the substrate during curing.

Example 10 can include, or can optionally be combined with the subjectmatter of one or any combination of Examples 1 through 9 to optionallyinclude an enclosed printing system and the enclosed curing moduleconfigured to provide controlled processing environments at or nearatmospheric pressure and established to remain below specified limits ofparticulate contamination level, water vapor content, and oxygencontent.

Example 11 can include, or can optionally be combined with the subjectmatter of one or any combination of Examples 1 through 10 to optionallyinclude a deposition region that includes a length dimension and a widthdimension, and an ultraviolet treatment region that comprises anultraviolet (UV) source including an array of UV emitters, the arrayhaving a span in at least one dimension that is greater than at leastone of the length dimension or the width dimension.

Example 12 can include, or can optionally be combined with the subjectmatter of Example 11, to optionally include an array of UV emitters thatextends in two dimensions.

Example 13 can include, or can optionally be combined with the subjectmatter of Example 11, to optionally include an array of UV emitterscomprising an array of light emitting diodes.

Example 14 can include, or can optionally be combined with the subjectmatter of one or any combination of Examples 1 through 13 to optionallyinclude an ultraviolet treatment region that comprises an ultraviolet(UV) source and a diffuser, the diffuser configured to normalize anintensity of the UV source across an area of the deposition regiontreated using the UV source.

Example 15 can include, or can optionally be combined with the subjectmatter of one or any combination of Examples 1 through 14 to optionallyinclude an enclosed curing is configured to control a temperature of thesubstrate in a manner to maintain a specified temperature uniformityacross the deposition region.

Example 16 can include, or can optionally be combined with the subjectmatter of one or any combination of Examples 1 through 15 to include,subject matter (such as an apparatus, a method, a means for performingacts, or a machine readable medium including instructions that, whenperformed by the machine, that can cause the machine to perform acts),such as can include providing a coating, comprising transferring asubstrate from an inorganic thin film encapsulation system to a transfermodule of an organic thin film encapsulation system, transferring thesubstrate to an enclosed printing system, the enclosed printing systemconfigured to deposit a patterned organic layer in a deposition regionon a first side of the substrate, the patterned organic layer coating atleast a portion of a light-emitting device fabricated upon thesubstrate, uniformly supporting the substrate in the enclosed printingsystem using a first gas cushion provided to a second side of thesubstrate opposite the deposition region, printing monomer over thedeposition region of the substrate using the enclosed printing system,transferring the substrate from the enclosed printing system to thetransfer module, transferring the substrate from the transfer module toan enclosed curing module, uniformly supporting the substrate in theenclosed curing module using a second gas cushion provided to the secondside of the substrate opposite the first side, and treating the monomerfilm layer in the enclosed curing module to provide a mura-freepolymerized organic layer in the deposition region.

Example 17 can include, or can optionally be combined with the subjectmatter of Example 16, to optionally include a deposition region on thefirst side of the substrate that overlaps with an active region of thesubstrate comprising the light-emitting device, and wherein at least oneof the first or second gas cushions is provided to the second side ofthe substrate opposite the active region.

Example 18 can include, or can optionally be combined with the subjectmatter of Example 17, to optionally include at least one of supportingthe substrate in the enclosed printing system or the enclosed curingmodule including using physical contact with the second side of thesubstrate, opposite the first side, where the physical contact is in anarea corresponding to a region outside the active region.

Example 19 can include, or can optionally be combined with the subjectmatter of one or any combination of Examples 16 through 18 to optionallyinclude treating the monomer layer including providing an ultraviolettreatment.

Example 20 can include, or can optionally be combined with the subjectmatter of Example 19, to optionally include a holding the substrate inthe enclosed curing module for a specified duration after deposition ofthe monomer layer and before ultraviolet treatment.

Example 21 can include, or can optionally be combined with the subjectmatter of one or any combination of Examples 16 through 20 to optionallyinclude transferring the substrate from the inorganic thin filmdeposition system to the transfer module of the organic thin filmdeposition system includes receiving the substrate from an atmosphericenvironment different from an environment of one or more of the printingsystem or the curing module.

Example 22 can include, or can optionally be combined with the subjectmatter of one or any combination of Examples 16 through 21 to optionallyinclude at least one of the first or second gas cushions establishedusing a porous ceramic material by forcing gas through the porousceramic material to support the second side of the substrate above theporous ceramic material.

Example 23 can include, or can optionally be combined with the subjectmatter of one or any combination of Examples 16 through 22 to optionallyinclude establishing at least one of the first or second gas cushionsusing pressurized gas.

Example 24 can include, or can optionally be combined with the subjectmatter of one or any combination of Examples 16 through 22 to optionallyinclude establishing at least one of the first or second gas cushionsusing a combination of a pressurized gas region and at least a partialvacuum region.

Example 25 can include, or can optionally be combined with the subjectmatter of one or any combination of Examples 16 through 24 to optionallyinclude the enclosed printing system and the enclosed curing moduleproviding controlled processing environments at or near atmosphericpressure and established to remain below specified limits of particulatecontamination level, water vapor content, and oxygen content.

Example 26 can include, or can optionally be combined with the subjectmatter of one or any combination of Examples 1 through 25 to include,subject matter (such as an apparatus, a method, a means for performingacts, or a machine readable medium including instructions that, whenperformed by the machine, that can cause the machine to perform acts),such as can include a coating system for providing a coating on asubstrate, the system comprising an enclosed printing system configuredto deposit a patterned organic layer on a substrate, the patternedorganic layer coating at least a portion of a light-emitting devicebeing fabricated upon the substrate, the enclosed first printing systemconfigured to provide a first processing environment, an enclosed curingmodule including a stacked configuration of ultraviolet treatmentregions, the ultraviolet treatment regions offset from each other andeach configured to accommodate a substrate, the enclosed curing moduleconfigured to provide a second processing environment, and an enclosedsubstrate transfer module comprising a chamber configured to receive thesubstrate from an atmospheric environment different from the environmentof one or more of the enclosed printing system or the enclosed curingmodule. In Example 26, the first and second processing environmentscomprise controlled environments at or near atmospheric pressure andestablished to remain below specified limits of limits of particulatecontamination level, water vapor content, and oxygen content.

Example 27 can include, or can optionally be combined with the subjectmatter of Example 26, to optionally include respective ones of theultraviolet treatment regions configured to hold the substrate for aspecified duration.

Example 28 can include, or can optionally be combined with the subjectmatter of one or any combination of Examples 26 or 27 to optionallyinclude respective ones of the ultraviolet treatment regions configuredto hold the substrate for a specified duration after deposition of thepatterned organic layer and before ultraviolet treatment.

Example 29 can include, or can optionally be combined with the subjectmatter of one or any combination of Examples 26 through 28 to optionallyinclude an enclosed holding module configured to provide a thirdprocessing environment comprising a controlled environment at or nearatmospheric pressure and established to remain below specified limits oflimits of particulate contamination level, water vapor content, andoxygen content, the enclosed holding module configured to hold thesubstrate when the substrate is transferred to the enclosed holdingmodule from one or more of the printing system or from elsewhere.

Example 30 can include, or can optionally be combined with the subjectmatter of one or any combination of Examples 26 through 29 to optionallyinclude a substrate oriented in a face-up configuration for depositionof the patterned organic layer on the upward-facing surface of thesubstrate.

Example 31 can include, or can optionally be combined with the subjectmatter of one or any combination of Examples 26 through 30 to optionallyinclude an atmospheric environment different from the environment of oneor more of the printing system or the curing module comprising a vacuum.

Example 32 can include, or can optionally be combined with the subjectmatter of one or any combination of Examples 26 through 31 to optionallyinclude a substrate loading module configured to transition thesubstrate to an environment above atmospheric pressure and to providethe substrate to the transfer module.

Example 33 can include, or can optionally be combined with the subjectmatter of one or any combination of Examples 26 through 32 to optionallyinclude a printing system comprising an inkjet printing system.

Example 34 can include, or can optionally be combined with the subjectmatter of one or any combination of Examples 26 through 33 to optionallyinclude first and second processing environments including anon-reactive gas specified for minimal or no reactivity with a speciesdeposited on the substrate.

Example 35 can include, or can optionally be combined with the subjectmatter of one or any combination of Examples 26 through 34 to optionallyinclude first and second processing environments comprising nitrogenabove atmospheric pressure.

Example 36 can include, or can optionally be combined with the subjectmatter of one or any combination of Examples 26 through 35 to optionallyinclude first and second processing environments established to maintainan environment having less than 100 parts-per-million of oxygen and lessthan 100 parts-per-million of water vapor.

Example 37 can include, or can optionally be combined with the subjectmatter of one or any combination of Examples 26 through 36 to optionallyinclude a particulate contamination level controlled at least in partusing multiple fan filter units located along or nearby a path traversedby the substrate.

Example 38 can include, or can optionally be combined with the subjectmatter of one or any combination of Examples 26 through 37 to optionallyinclude first and second processing environments are substantially thesame.

Each of the non-limiting examples described herein can stand on its own,or can be combined in various permutations or combinations with one ormore of the other examples.

The above detailed description includes references to the accompanyingdrawings, which form a part of the detailed description. The drawingsshow, by way of illustration, specific embodiments in which theinvention can be practiced. These embodiments are also referred toherein as “examples.” Such examples can include elements in addition tothose shown or described. However, the present inventors alsocontemplate examples in which only those elements shown or described areprovided. Moreover, the present inventors also contemplate examplesusing any combination or permutation of those elements shown ordescribed (or one or more aspects thereof), either with respect to aparticular example (or one or more aspects thereof), or with respect toother examples (or one or more aspects thereof) shown or describedherein. In the event of inconsistent usages between this document andany documents so incorporated by reference, the usage in this documentcontrols.

In this document, the terms “a” or “an” are used, as is common in patentdocuments, to include one or more than one, independent of any otherinstances or usages of “at least one” or “one or more.” In thisdocument, the term “or” is used to refer to a nonexclusive or, such that“A or B” includes “A but not B,” “B but not A,” and “A and B,” unlessotherwise indicated. In this document, the terms “including” and “inwhich” are used as the plain-English equivalents of the respective terms“comprising” and “wherein.” Also, in the following claims, the terms“including” and “comprising” are open-ended, that is, a system, device,article, composition, formulation, or process that includes elements inaddition to those listed after such a term in a claim are still deemedto fall within the scope of that claim. Moreover, in the followingclaims, the terms “first,” “second,” and “third,” etc. are used merelyas labels, and are not intended to impose numerical requirements ontheir objects.

Method examples described herein can be machine or computer-implementedat least in part. Some examples can include a computer-readable mediumor machine-readable medium encoded with instructions operable toconfigure an electronic device to perform methods as described in theabove examples. An implementation of such methods can include code, suchas microcode, assembly language code, a higher-level language code, orthe like. Such code can include computer readable instructions forperforming various methods. The code may form portions of computerprogram products. Further, in an example, the code can be tangiblystored on one or more volatile, non-transitory, or non-volatile tangiblecomputer-readable media, such as during execution or at other times.Examples of these tangible computer-readable media can include, but arenot limited to, hard disks, removable magnetic disks, removable opticaldisks (e.g., compact disks and digital video disks), magnetic cassettes,memory cards or sticks, random access memories (RAMs), read onlymemories (ROMs), and the like.

The above description is intended to be illustrative, and notrestrictive. For example, the above-described examples (or one or moreaspects thereof) may be used in combination with each other. Otherembodiments can be used, such as by one of ordinary skill in the artupon reviewing the above description. The Abstract is provided to complywith 37 C.F.R. §1.72(b), to allow the reader to quickly ascertain thenature of the technical disclosure. It is submitted with theunderstanding that it will not be used to interpret or limit the scopeor meaning of the claims. Also, in the above Detailed Description,various features may be grouped together to streamline the disclosure.This should not be interpreted as intending that an unclaimed disclosedfeature is essential to any claim. Rather, inventive subject matter maylie in less than all features of a particular disclosed embodiment.Thus, the following claims are hereby incorporated into the DetailedDescription as examples or embodiments, with each claim standing on itsown as a separate embodiment, and it is contemplated that suchembodiments can be combined with each other in various combinations orpermutations. The scope of the invention should be determined withreference to the appended claims, along with the full scope ofequivalents to which such claims are entitled.

What is claimed is:
 1. A method for providing a substrate coating,comprising: transferring a substrate to an enclosed ink jet printingsystem, wherein the enclosed ink jet printing system is configured todeposit a patterned organic material in a deposition region over atleast a portion of an active region of a light-emitting devicefabricated upon the substrate; printing organic material over thedeposition region of the substrate using the enclosed printing system;transferring the substrate with the patterned organic material depositedthereon to an enclosed curing module, wherein the enclosed curing moduleis configured to provide an ultraviolet treatment to treat the organicmaterial deposited on the substrate to form a solid organic film layer;supporting the substrate in the enclosed curing module using apressurized gas cushion distributed between the substrate and asubstrate support apparatus, the pressurized gas cushion beingsufficient to float the substrate above the substrate support apparatus;and treating the organic material deposited on the substrate with anultraviolet treatment using the enclosed curing module to form anorganic film layer.
 2. The method of claim 1, further comprising, aftertransferring the substrate into an enclosed ink jet printing system:supporting the substrate in the enclosed printing system using a firstpressurized gas cushion distributed between the substrate and a firstsubstrate support apparatus to float the substrate above the firstsubstrate support apparatus; wherein supporting the substrate in theenclosed curing module comprises using a second pressurized gas cushiondistributed between the substrate and a second substrate supportapparatus to float the substrate above the second substrate supportapparatus.
 3. The method of claim 2, wherein supporting the substrateusing at least one of the first distributed pressurized gas cushion andthe second distributed pressurized gas cushion suppresses mura on theformed organic film layer.
 4. The method of claim 2, wherein supportingthe substrate in at least one of the enclosed printing system and theenclosed curing module comprises forcing gas through a porous ceramicmaterial to distribute the pressurized gas cushion used to float thesubstrate.
 5. The method of claim 2, comprising establishing at leastone of the first distributed pressurized gas cushion and the seconddistributed pressurized gas cushion using a non-reactive pressurizedgas.
 6. The method of claim 2, comprising establishing at least one ofthe first distributed pressurized gas cushion and the second distributedpressurized gas cushion using a combination of a pressurizednon-reactive gas region and at least a partial vacuum region.
 7. Themethod of claim 2, wherein supporting the substrate in at least one ofthe enclosed printing system and the enclosed curing module additionallycomprises physically contacting the substrate with a support structure.8. The method of claim 7, wherein physically contacting the substratewith the support structure is in an area corresponding to a regionoutside of the active region of the light-emitting device fabricatedupon the substrate.
 9. The method of claim 7, wherein the supportstructure comprises at least one lift pin.
 10. The method of claim 1,further comprising while supporting the substrate in the enclosed curingmodule, retaining the substrate at a periphery of the substrate torestrict lateral translation of the substrate while supporting thesubstrate by the pressurized gas cushion.
 11. The method of claim 1,further comprising holding the substrate in the enclosed curing modulefor a specified duration before treating the organic material on thesubstrate.
 12. The method of claim 1, further comprising, after printingorganic material over the deposition region of the substrate:transferring the substrate with the patterned organic material depositedthereon from the enclosed inkjet printing system to an enclosed holdingmodule; and holding the substrate for a specified duration in theenclosed holding module; wherein the transferring of the substrate withthe patterned organic material deposited thereon to the enclosed curingmodule comprises transferring the substrate with the patterned organicmaterial thereon from the holding module to the enclosed curing module.13. The method of claim 12, further comprising, after transferring thesubstrate to the enclosed holding module: supporting the substrate inthe enclosed holding module using a first pressurized gas cushiondistributed between the substrate and a first substrate supportapparatus to float the substrate above the first substrate supportapparatus; wherein supporting the substrate in the enclosed curingmodule comprises using a second pressurized gas cushion distributedbetween the substrate and a second substrate support apparatus to floatthe substrate above the second substrate support apparatus.
 14. Themethod of claim 1, further comprising providing a controlled processingenvironment for each of the enclosed printing system and the enclosedcuring module.
 15. The method of claim 14, wherein the controlledprocessing environments are maintained below specified limits ofreactive gaseous species.
 16. The method of claim 15, wherein thereactive gaseous species are water vapor, ozone, and oxygen that aremaintained below 100 parts-per-million for each species.
 17. The methodof claim 14, wherein the controlled processing environments aremaintained below specified limits of particulate contamination level.18. The method of claim 17, wherein the particulate contamination levelis controlled at least in part using multiple fan filter units locatedalong or nearby a path traversed by the substrate.
 19. The method ofclaim 14, wherein the controlled processing environments are gasenvironments at or near atmospheric pressure.
 20. The method of claim19, wherein the controlled gas environment is a non-reactive gasenvironment.
 21. The method of claim 20, wherein the non-reactive gasenvironment is maintained using nitrogen.